Innovative and butt ends

[Sid 3]

I have a 1100 O shape and an 1100 5 shape dual fit both for standard blades. My question is do all butt ends for 5 shape or others have to be shaved down or do some shapes accept standard butt ends?

Thnaks Sid

[thejackal 46]

They're a bit skinnier on the top and bottom.