diff --git a/src/FSharpPlus/Control/Functor.fs b/src/FSharpPlus/Control/Functor.fs
index f33218683..7534d5193 100644
--- a/src/FSharpPlus/Control/Functor.fs
+++ b/src/FSharpPlus/Control/Functor.fs
@@ -233,10 +233,10 @@ type Zip =
         call (Unchecked.defaultof<Zip>, source1, source2) : '``ZipFunctor<'T1 * 'T2>``
 
     static member inline InvokeOnInstance (source1: '``ZipFunctor<'T1>``) (source2: '``ZipFunctor<'T2>``) : '``ZipFunctor<'T1 * 'T2>`` =
-        ((^``ZipFunctor<'T1>`` or ^``ZipFunctor<'T2>`` or  ^``ZipFunctor<'T1 * 'T2>``) : (static member Zip : _*_ -> _) source1, source2)
+        ((^``ZipFunctor<'T1>`` or ^``ZipFunctor<'T2>``) : (static member Zip : _*_ -> _) source1, source2)
 
-type Zip with    
-    static member inline Zip ((_: ^t when ^t : null and ^t: struct, _: ^u when ^u : null and ^u: struct, _output: ^r when ^r : null and ^r: struct), _mthd: Default1) = id
+type Zip with
+    static member inline Zip ((x: '``ZipFunctor<'T1>``            , y: '``ZipFunctor<'T2>``            , _output: '``ZipFunctor<'T1 * 'T2>``      ), _mthd: Default2) = ZipApply.Invoke (Map.Invoke (fun a b -> (a, b)) x) y
     static member inline Zip ((x: '``ZipFunctor<'T1>``            , y: '``ZipFunctor<'T2>``            , _output: '``ZipFunctor<'T1 * 'T2>``      ), _mthd: Default1) = Zip.InvokeOnInstance x y : '``ZipFunctor<'T1 * 'T2>``
 
 #endif