diff --git a/src/Data/Base/ToArrayObject.php b/src/Data/Base/ToArrayObject.php
index 5ebf04f9..dba550b2 100644
--- a/src/Data/Base/ToArrayObject.php
+++ b/src/Data/Base/ToArrayObject.php
@@ -2,6 +2,7 @@
 
 namespace Jasara\AmznSPA\Data\Base;
 
+use BackedEnum;
 use Carbon\CarbonImmutable;
 use Illuminate\Support\Collection;
 use Illuminate\Support\Str;
@@ -50,8 +51,10 @@ private function mapPropertyValue(
         return match (true) {
             $has_mapper => $this->mapWithMapper($property, $value),
             $value instanceof Data => $this->mapWithData($case, $value),
+            $value instanceof TypedCollection => $value->toArrayObject(),
             $value instanceof Collection => $this->mapWithCollection($case, $value),
             $value instanceof CarbonImmutable => $this->mapWithCarbonImmutable($value),
+            $value instanceof BackedEnum => $value->value,
             default => $value,
         };
     }
diff --git a/src/Data/Base/TypedCollection.php b/src/Data/Base/TypedCollection.php
index 61fc7ef7..f8308cc6 100644
--- a/src/Data/Base/TypedCollection.php
+++ b/src/Data/Base/TypedCollection.php
@@ -2,6 +2,7 @@
 
 namespace Jasara\AmznSPA\Data\Base;
 
+use BackedEnum;
 use Illuminate\Support\Arr;
 use Illuminate\Support\Collection;
 
@@ -54,4 +55,17 @@ public function reduce(callable $callback, $initial = null)
     {
         return $this->toBase()->reduce($callback, $initial);
     }
+
+    public function toArrayObject(): \ArrayObject
+    {
+        return new \ArrayObject($this->map(function ($item) {
+            return match (true) {
+                $item instanceof TypedCollection => $item->toArrayObject(),
+                $item instanceof Collection => $item->toArrayObject(),
+                $item instanceof Data => $item->toArrayObject(),
+                $item instanceof BackedEnum => $item->value,
+                default => $item,
+            };
+        })->toArray());
+    }
 }
diff --git a/src/Data/Responses/FulfillmentInbound/v20240320/ListPrepDetailsResponse.php b/src/Data/Responses/FulfillmentInbound/v20240320/ListPrepDetailsResponse.php
new file mode 100644
index 00000000..65db5521
--- /dev/null
+++ b/src/Data/Responses/FulfillmentInbound/v20240320/ListPrepDetailsResponse.php
@@ -0,0 +1,14 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320;
+
+use Jasara\AmznSPA\Data\Responses\BaseResponse;
+use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\MskuPrepDetailSchemaList;
+
+class ListPrepDetailsResponse extends BaseResponse
+{
+    public function __construct(
+        public MskuPrepDetailSchemaList $msku_prep_details,
+    ) {
+    }
+}
diff --git a/src/Data/Responses/FulfillmentInbound/v20240320/SetPrepDetailsResponse.php b/src/Data/Responses/FulfillmentInbound/v20240320/SetPrepDetailsResponse.php
new file mode 100644
index 00000000..80f766dd
--- /dev/null
+++ b/src/Data/Responses/FulfillmentInbound/v20240320/SetPrepDetailsResponse.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320;
+
+use Jasara\AmznSPA\Data\Base\Validators\RuleValidator;
+use Jasara\AmznSPA\Data\Responses\BaseResponse;
+
+class SetPrepDetailsResponse extends BaseResponse
+{
+    public function __construct(
+        #[RuleValidator(['min:36', 'max:38'])]
+        public ?string $operation_id,
+    ) {
+    }
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/AllOwnersConstraint.php b/src/Data/Schemas/FulfillmentInbound/v20240320/AllOwnersConstraint.php
new file mode 100644
index 00000000..d5b0a240
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/AllOwnersConstraint.php
@@ -0,0 +1,8 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+enum AllOwnersConstraint: string
+{
+    case MustMatch = 'MUST_MATCH';
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailInputSchema.php b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailInputSchema.php
new file mode 100644
index 00000000..9ddfad3b
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailInputSchema.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+use Jasara\AmznSPA\Data\Schemas\BaseSchema;
+
+class MskuPrepDetailInputSchema extends BaseSchema
+{
+    public function __construct(
+        public string $msku,
+        public PrepCategory $prep_category,
+        public PrepTypeList $prep_types,
+    ) {
+    }
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailInputSchemaList.php b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailInputSchemaList.php
new file mode 100644
index 00000000..52de7493
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailInputSchemaList.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+use Jasara\AmznSPA\Data\Base\TypedCollection;
+
+/**
+ * @template-extends TypedCollection<MskuPrepDetailInputSchema>
+ */
+class MskuPrepDetailInputSchemaList extends TypedCollection
+{
+    public const ITEM_CLASS = MskuPrepDetailInputSchema::class;
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailSchema.php b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailSchema.php
new file mode 100644
index 00000000..8e20e600
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailSchema.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+use Jasara\AmznSPA\Data\Schemas\BaseSchema;
+
+class MskuPrepDetailSchema extends BaseSchema
+{
+    public function __construct(
+        public ?AllOwnersConstraint $all_owners_constraint,
+        public ?OwnerConstraint $label_owner_constraint,
+        public string $msku,
+        public PrepCategory $prep_category,
+        public PrepTypeList $prep_types,
+        public ?OwnerConstraint $prep_owner_constraint,
+    ) {
+    }
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailSchemaList.php b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailSchemaList.php
new file mode 100644
index 00000000..3dba59c0
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/MskuPrepDetailSchemaList.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+use Jasara\AmznSPA\Data\Base\TypedCollection;
+
+/**
+ * @template-extends TypedCollection<MskuPrepDetailSchema>
+ */
+class MskuPrepDetailSchemaList extends TypedCollection
+{
+    public const ITEM_CLASS = MskuPrepDetailSchema::class;
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/OwnerConstraint.php b/src/Data/Schemas/FulfillmentInbound/v20240320/OwnerConstraint.php
new file mode 100644
index 00000000..3c009dfd
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/OwnerConstraint.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+enum OwnerConstraint: string
+{
+    case AmazonOnly = 'AMAZON_ONLY';
+    case SellerOnly = 'SELLER_ONLY';
+    case NoneOnly = 'NONE_ONLY';
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/PrepCategory.php b/src/Data/Schemas/FulfillmentInbound/v20240320/PrepCategory.php
new file mode 100644
index 00000000..6aa6b0cc
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/PrepCategory.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+enum PrepCategory: string
+{
+    case Adult = 'ADULT';
+    case Baby = 'BABY';
+    case FcProvided = 'FC_PROVIDED';
+    case Fragile = 'FRAGILE';
+    case Granular = 'GRANULAR';
+    case Hanger = 'HANGER';
+    case Liquid = 'LIQUID';
+    case Perforated = 'PERFORATED';
+    case Set = 'SET';
+    case Sharp = 'SHARP';
+    case Small = 'SMALL';
+    case Textile = 'TEXTILE';
+    case Unknown = 'UNKNOWN';
+    case None = 'NONE';
+}
diff --git a/src/Data/Schemas/FulfillmentInbound/v20240320/PrepTypeList.php b/src/Data/Schemas/FulfillmentInbound/v20240320/PrepTypeList.php
new file mode 100644
index 00000000..51034eaa
--- /dev/null
+++ b/src/Data/Schemas/FulfillmentInbound/v20240320/PrepTypeList.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320;
+
+use Jasara\AmznSPA\Data\Base\TypedCollection;
+
+/**
+ * @template-extends TypedCollection<PrepType>
+ */
+class PrepTypeList extends TypedCollection
+{
+    public const ITEM_CLASS = PrepType::class;
+}
diff --git a/src/Resources/FulfillmentInbound/FulfillmentInbound20240320Resource.php b/src/Resources/FulfillmentInbound/FulfillmentInbound20240320Resource.php
index d5369f29..c721dfe9 100644
--- a/src/Resources/FulfillmentInbound/FulfillmentInbound20240320Resource.php
+++ b/src/Resources/FulfillmentInbound/FulfillmentInbound20240320Resource.php
@@ -52,6 +52,7 @@
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPackingGroupItemsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPackingOptionsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPlacementOptionsResponse;
+use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPrepDetailsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListShipmentBoxesResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListShipmentContentUpdatePreviewsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListShipmentItemsResponse;
@@ -59,12 +60,14 @@
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListTransportationOptionsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ScheduleSelfShipAppointmentResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\SetPackingInformationResponse;
+use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\SetPrepDetailsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateItemComplianceDetailsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateShipmentDeliveryWindowResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateShipmentSourceAddressResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateShipmentTrackingDetailsResponse;
 use Jasara\AmznSPA\Data\Schemas\Common\SortOrder;
 use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\InboundPlanStatus;
+use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\MskuPrepDetailInputSchemaList;
 use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\SortBy;
 use Jasara\AmznSPA\Traits\ValidatesParameters;
 
@@ -525,7 +528,7 @@ public function listPackingGroupItems(
             ->responseClass(ListPackingGroupItemsResponse::class)
             ->get(
                 $this->endpoint . self::BASE_PATH . 'inboundPlans/' . $inbound_plan_id
-                . '/packingGroups/' . $packing_group_id 
+                . '/packingGroups/' . $packing_group_id
                 . '/items',
                 array_filter([
                     'pageSize' => $page_size,
@@ -861,4 +864,37 @@ public function getInboundOperationStatus(
 
         return $response;
     }
+
+    public function listPrepDetails(
+        string $marketplace_id,
+        #[RuleValidator(['min:1', 'max:100'])]
+        array $mskus,
+    ): ListPrepDetailsResponse {
+        $this->validateAttributes(__FUNCTION__, ...func_get_args());
+
+        $response = $this->http
+            ->responseClass(ListPrepDetailsResponse::class)
+            ->get($this->endpoint . self::BASE_PATH . 'prepDetails', [
+                'marketplaceId' => $marketplace_id,
+                'mskus' => $mskus,
+            ]);
+
+        return $response;
+    }
+
+    public function setPrepDetails(
+        string $marketplace_id,
+        MskuPrepDetailInputSchemaList $msku_prep_details,
+    ): SetPrepDetailsResponse {
+        $this->validateAttributes(__FUNCTION__, ...func_get_args());
+
+        $response = $this->http
+            ->responseClass(SetPrepDetailsResponse::class)
+            ->post($this->endpoint . self::BASE_PATH . 'items/prepDetails', [
+                'marketplaceId' => $marketplace_id,
+                'mskuPrepDetails' => $msku_prep_details->toArrayObject(),
+            ]);
+
+        return $response;
+    }
 }
diff --git a/tests/Unit/Resources/FulfillmentInbound/FulfillmentInbound20240320ResourceTest.php b/tests/Unit/Resources/FulfillmentInbound/FulfillmentInbound20240320ResourceTest.php
index db21c60b..3d3e41f3 100644
--- a/tests/Unit/Resources/FulfillmentInbound/FulfillmentInbound20240320ResourceTest.php
+++ b/tests/Unit/Resources/FulfillmentInbound/FulfillmentInbound20240320ResourceTest.php
@@ -50,6 +50,7 @@
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPackingGroupItemsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPackingOptionsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPlacementOptionsResponse;
+use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListPrepDetailsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListShipmentBoxesResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListShipmentContentUpdatePreviewsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListShipmentItemsResponse;
@@ -57,10 +58,16 @@
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ListTransportationOptionsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\ScheduleSelfShipAppointmentResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\SetPackingInformationResponse;
+use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\SetPrepDetailsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateItemComplianceDetailsResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateShipmentDeliveryWindowResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateShipmentSourceAddressResponse;
 use Jasara\AmznSPA\Data\Responses\FulfillmentInbound\v20240320\UpdateShipmentTrackingDetailsResponse;
+use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\MskuPrepDetailInputSchema;
+use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\MskuPrepDetailInputSchemaList;
+use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\PrepCategory;
+use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\PrepType;
+use Jasara\AmznSPA\Data\Schemas\FulfillmentInbound\v20240320\PrepTypeList;
 use Jasara\AmznSPA\Resources\FulfillmentInbound\FulfillmentInbound20240320Resource;
 use Jasara\AmznSPA\Tests\Unit\UnitTestCase;
 use PHPUnit\Framework\Attributes\CoversClass;
@@ -1087,4 +1094,64 @@ public function testCreateMarketplaceItemLabels(): void
             return true;
         });
     }
+
+    public function testListPrepDetails(): void
+    {
+        [$config, $http] = $this->setupConfigWithFakeHttp('fulfillment-inbound/v20240320/list-prep-details');
+
+        $mskus = ['msku1', 'msku2'];
+
+        $amzn = new AmznSPA($config);
+        $amzn = $amzn->usingMarketplace('ATVPDKIKX0DER');
+        $response = $amzn->fulfillment_inbound20240320->listPrepDetails(
+            marketplace_id: 'ATVPDKIKX0DER',
+            mskus: $mskus,
+        );
+
+        $this->assertInstanceOf(ListPrepDetailsResponse::class, $response);
+        $this->assertEquals('msku1', $response->msku_prep_details[0]->msku);
+
+        $http->assertSent(function (Request $request) use ($mskus) {
+            $this->assertEquals('GET', $request->method());
+            $this->assertEquals('https://sellingpartnerapi-na.amazon.com/inbound/fba/2024-03-20/prepDetails?marketplaceId=ATVPDKIKX0DER&mskus=msku1,msku2', urldecode($request->url()));
+
+            return true;
+        });
+    }
+
+    public function testSetPrepDetails(): void
+    {
+        [$config, $http] = $this->setupConfigWithFakeHttp('fulfillment-inbound/v20240320/set-prep-details');
+
+        $msku_prep_details = MskuPrepDetailInputSchemaList::make([
+            new MskuPrepDetailInputSchema(
+                msku: 'msku1',
+                prep_category: PrepCategory::Sharp,
+                prep_types: PrepTypeList::make([
+                    PrepType::Sharp,
+                ]),
+            ),
+        ]);
+
+        $amzn = new AmznSPA($config);
+        $amzn = $amzn->usingMarketplace('ATVPDKIKX0DER');
+        $response = $amzn->fulfillment_inbound20240320->setPrepDetails(
+            marketplace_id: 'ATVPDKIKX0DER',
+            msku_prep_details: $msku_prep_details,
+        );
+
+        $this->assertInstanceOf(SetPrepDetailsResponse::class, $response);
+        $this->assertEquals('1234abcd-1234-abcd-5678-1234abcd1102', $response->operation_id);
+
+        $http->assertSent(function (Request $request) use ($msku_prep_details) {
+            $this->assertEquals('POST', $request->method());
+            $this->assertEquals('https://sellingpartnerapi-na.amazon.com/inbound/fba/2024-03-20/items/prepDetails', (string) $request->url());
+            $this->assertEquals('ATVPDKIKX0DER', $request->data()['marketplaceId']);
+            ray($request->data());
+            $this->assertEquals('SHARP', $request->data()['mskuPrepDetails'][0]['prepCategory']);
+            $this->assertEquals('SHARP', $request->data()['mskuPrepDetails'][0]['prepTypes'][0]);
+
+            return true;
+        });
+    }
 }
diff --git a/tests/stubs/fulfillment-inbound/v20240320/list-prep-details.json b/tests/stubs/fulfillment-inbound/v20240320/list-prep-details.json
new file mode 100644
index 00000000..2a9182d7
--- /dev/null
+++ b/tests/stubs/fulfillment-inbound/v20240320/list-prep-details.json
@@ -0,0 +1,24 @@
+{
+    "mskuPrepDetails": [
+        {
+            "msku": "msku1",
+            "prepCategory": "TEXTILE",
+            "prepTypes": [
+                "ITEM_LABELING",
+                "ITEM_POLYBAGGING"
+            ],
+            "prepOwnerConstraint": "AMAZON_ONLY",
+            "labelOwnerConstraint": "AMAZON_ONLY",
+            "allOwnersConstraint": "MUST_MATCH"
+        },
+        {
+            "msku": "msku2",
+            "prepCategory": "FRAGILE",
+            "prepTypes": [
+                "ITEM_LABELING",
+                "ITEM_BUBBLEWRAP"
+            ],
+            "allOwnersConstraint": "MUST_MATCH"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/tests/stubs/fulfillment-inbound/v20240320/set-prep-details.json b/tests/stubs/fulfillment-inbound/v20240320/set-prep-details.json
new file mode 100644
index 00000000..43590c04
--- /dev/null
+++ b/tests/stubs/fulfillment-inbound/v20240320/set-prep-details.json
@@ -0,0 +1,3 @@
+{
+    "operationId": "1234abcd-1234-abcd-5678-1234abcd1102"
+}
\ No newline at end of file