Latch for storm windows

Thanks for posting. I'm actually not sure which latch would be the best replacement option. My first thought would be our 91-006, however looking at your photos, your latches do not look worn. My feeling is that the problem could be in the storm window track itself. Check the notches or cut outs in the side track of the storm window to see if they're worn. In some cases, I've used a small sharp chisel and hammer to re work the notches, when necessary. You just have to be careful you don't damage the window in the process.