diff --git a/tox.ini b/tox.ini
index 1b703c7c..f6428562 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,8 +7,8 @@ commands =
   make flake8
   coverage run --append -m pytest -v -s tests/
 deps = 
-    flake8
-    black
+    flake8==3.8.3
+    black==19.10b0
     netaddr
     mock
     coverage