Replacement window crank

Hey, Larry. If I understand you correctly, you need a new handle for your casement window operator. We sell a couple handles separately, like our 39-205, but it looks like you need a cover, too. 

Consider our 39-375, which is a handle/cover combo. This is designed to work with operators that have an 11/32" spline. That's basically just the diameter of the hole in the old handle. If you measure your old handle's hole and you get 11/32" then the 39-375 should work for you.

Yep, that assembly is what we call an operator. The cover snaps over top of it.

As for providing a seal, I suppose it does but if you find there to be a draft issue then a cover alone may not be sufficient. Operators like yours usually have a gasket around the hole that helps to that effect. You may want to consider our 39-563, which is made to work with operators like yours. 

Using something like this is a better long-term solution than caulking, in my opinion. Should the operator ever need to be replaced in the future, removing a simple gasket like this is a whoooole lot easier than removing caulking.