This older ? Storm window hardware the plastic piece slides in a track on the window frame and has spring loaded latch to lock slide in place in track don't know the brand and haven't seen in the hw stores Thanks
Lauren from SWISCO responded:
October 28, 2021
Hello, thank you for posting!
Your latches resemble our 91-054 slide bolt pair and 91-003 spring. Please review the dimensions below for a good fit!