diff --git a/spacy/tests/serialize/test_serialize_tagger.py b/spacy/tests/serialize/test_serialize_tagger.py
index fa9a776bb..e56db1421 100644
--- a/spacy/tests/serialize/test_serialize_tagger.py
+++ b/spacy/tests/serialize/test_serialize_tagger.py
@@ -11,8 +11,8 @@ import pytest
 def taggers(en_vocab):
     tagger1 = Tagger(en_vocab)
     tagger2 = Tagger(en_vocab)
-    tagger1.model = tagger1.Model(None, None)
-    tagger2.model = tagger2.Model(None, None)
+    tagger1.model = tagger1.Model(8, 8)
+    tagger2.model = tagger2.Model(8, 8)
     return (tagger1, tagger2)