Window sash lock, possibly a weather shield product
A landlord from Black river falls wi says:
July 31, 2019
Sash lock locks into hole in frame of upper sash.
Bob from SWISCO responded:
August 5, 2019
Thanks for writing in. Our 90-009 might be what you're looking for. This is made to lock into a keeper like our 90-109. Let me know if this looks like it could work for you.