diff --git a/geozero/src/mvt/mod.rs b/geozero/src/mvt/mod.rs
index d0a30d0c..e28b1539 100644
--- a/geozero/src/mvt/mod.rs
+++ b/geozero/src/mvt/mod.rs
@@ -26,32 +26,36 @@ pub(crate) mod conversion {
     /// Convert to MVT geometry.
     pub trait ToMvt {
         /// Convert to MVT geometry.
+        ///
+        /// # Arguments
+        /// * `extent` - Size of MVT tile in tile coordinate space (e.g. 4096).
+        /// * `left`, `bottom`, `right`, `top` - Bounds of tile in map coordinate space, with no buffer.
         fn to_mvt(
             &self,
-            tile_size: u32,
+            extent: u32,
             left: f64,
             bottom: f64,
             right: f64,
             top: f64,
         ) -> Result<tile::Feature>;
-        /// Convert to MVT geometry with geometries in tile coordinate system.
-        fn to_mvt_unscaled(&self) -> Result<tile::Feature>;
+        /// Convert to MVT geometry with geometries in tile coordinate space.
+        fn to_mvt_raw(&self) -> Result<tile::Feature>;
     }
 
     impl<T: GeozeroGeometry> ToMvt for T {
         fn to_mvt(
             &self,
-            tile_size: u32,
+            extent: u32,
             left: f64,
             bottom: f64,
             right: f64,
             top: f64,
         ) -> Result<tile::Feature> {
-            let mut mvt = MvtWriter::new(tile_size, left, bottom, right, top);
+            let mut mvt = MvtWriter::new(extent, left, bottom, right, top);
             self.process_geom(&mut mvt)?;
             Ok(mvt.feature)
         }
-        fn to_mvt_unscaled(&self) -> Result<tile::Feature> {
+        fn to_mvt_raw(&self) -> Result<tile::Feature> {
             let mut mvt = MvtWriter::default();
             self.process_geom(&mut mvt)?;
             Ok(mvt.feature)
diff --git a/geozero/src/mvt/mvt_writer.rs b/geozero/src/mvt/mvt_writer.rs
index cea065ea..b013b3e5 100644
--- a/geozero/src/mvt/mvt_writer.rs
+++ b/geozero/src/mvt/mvt_writer.rs
@@ -415,21 +415,21 @@ mod test {
     #[test]
     fn point_geom() {
         let geojson = GeoJson(r#"{"type": "Point", "coordinates": [25, 17]}"#);
-        let mvt = geojson.to_mvt_unscaled().unwrap();
+        let mvt = geojson.to_mvt_raw().unwrap();
         assert_eq!(mvt.geometry, [9, 50, 34]);
     }
 
     #[test]
     fn multipoint_geom() {
         let geojson = GeoJson(r#"{"type": "MultiPoint", "coordinates": [[5, 7], [3, 2]]}"#);
-        let mvt = geojson.to_mvt_unscaled().unwrap();
+        let mvt = geojson.to_mvt_raw().unwrap();
         assert_eq!(mvt.geometry, [17, 10, 14, 3, 9]);
     }
 
     #[test]
     fn line_geom() {
         let geojson = GeoJson(r#"{"type": "LineString", "coordinates": [[2,2], [2,10], [10,10]]}"#);
-        let mvt = geojson.to_mvt_unscaled().unwrap();
+        let mvt = geojson.to_mvt_raw().unwrap();
         assert_eq!(mvt.geometry, [9, 4, 4, 18, 0, 16, 16, 0]);
     }
 
@@ -438,7 +438,7 @@ mod test {
         let geojson = GeoJson(
             r#"{"type": "MultiLineString", "coordinates": [[[2,2], [2,10], [10,10]],[[1,1],[3,5]]]}"#,
         );
-        let mvt = geojson.to_mvt_unscaled().unwrap();
+        let mvt = geojson.to_mvt_raw().unwrap();
         assert_eq!(
             mvt.geometry,
             [9, 4, 4, 18, 0, 16, 16, 0, 9, 17, 17, 10, 4, 8]
@@ -449,7 +449,7 @@ mod test {
     fn polygon_geom() {
         let geojson =
             GeoJson(r#"{"type": "Polygon", "coordinates": [[[3, 6], [8, 12], [20, 34], [3, 6]]]}"#);
-        let mvt = geojson.to_mvt_unscaled().unwrap();
+        let mvt = geojson.to_mvt_raw().unwrap();
         assert_eq!(mvt.geometry, [9, 6, 12, 18, 10, 12, 24, 44, 15]);
     }
 
@@ -472,7 +472,7 @@ mod test {
             ]
         }"#;
         let geojson = GeoJson(geojson);
-        let mvt = geojson.to_mvt_unscaled().unwrap();
+        let mvt = geojson.to_mvt_raw().unwrap();
         assert_eq!(
             mvt.geometry,
             [
@@ -485,7 +485,7 @@ mod test {
     #[cfg(feature = "with-geo")]
     fn geo_screen_coords_to_mvt() -> Result<()> {
         let geo: geo_types::Geometry<f64> = geo_types::Point::new(25.0, 17.0).into();
-        let mvt = geo.to_mvt_unscaled()?;
+        let mvt = geo.to_mvt_raw()?;
         assert_eq!(mvt.geometry, [9, 50, 34]);
         Ok(())
     }
diff --git a/geozero/tests/mvt.rs b/geozero/tests/mvt.rs
index 490e2c0b..6003d40d 100644
--- a/geozero/tests/mvt.rs
+++ b/geozero/tests/mvt.rs
@@ -11,7 +11,7 @@ use std::sync::Mutex;
 #[test]
 fn geo_screen_coords_to_mvt() {
     let geo: geo_types::Geometry<f64> = geo_types::Point::new(25.0, 17.0).into();
-    let mvt = geo.to_mvt_unscaled().unwrap();
+    let mvt = geo.to_mvt_raw().unwrap();
     assert_eq!(mvt.geometry, [9, 50, 34]);
 }