Paul from SWISCO responded:
November 15, 2016
Thanks for posting! Our 90-278, and most similarly designed locks, are made of die cast metal.
I'm not sure why your locks are breaking, but one reason could be because the upper sash might be hanging down a little (it would almost look like the top sash is "smiling"). What I've done in the past was shim up the keeper, that might help it interact with the lock more comfortably and prevent your future locks from breaking so easily. |