diff --git a/src/Math/Vector4.h b/src/Math/Vector4.h
index 0df339f24..e7b21e320 100644
--- a/src/Math/Vector4.h
+++ b/src/Math/Vector4.h
@@ -86,7 +86,7 @@ template<class T> class Vector4: public Vector<4, T> {
         inline constexpr Vector2<T> xy() const { return Vector2<T>::from(Vector<4, T>::data()); } /**< @overload */
 
         MAGNUM_VECTOR_SUBCLASS_IMPLEMENTATION(Vector4, 4)
-        MAGNUM_RECTANGULARMATRIX_SUBCLASS_OPERATOR_IMPLEMENTATION(1, 3, Vector4<T>)
+        MAGNUM_RECTANGULARMATRIX_SUBCLASS_OPERATOR_IMPLEMENTATION(1, 4, Vector4<T>)
 };
 
 MAGNUM_VECTOR_SUBCLASS_OPERATOR_IMPLEMENTATION(Vector4, 4)