Sorry. No markings. Windows were installed approx 1973. Florida condo.

Single hung aluminum sash using block and tackle balance. The nylon part at the top corners of the sash serve to capture the block and tackle when the window is pulled down. The sliding tab slips into the block and tackle end cap to prevent accidentally disengaging from b&t when sash is raised to its limit. Nylon piece is secured to the side of the sash with a single screw.

I'm looking to replace approx 1 dozen broken thing-a-ma-bobs.

Looks the same. I will measure just to be certain before ordering. Thanks!

Confirmed the measurements and ordered. I decided to replace the guides in all six windows since they are all decades old & likely to be near their end-of-life.

The Parts Identifier option is a great service. Sometimes it is a huge help to a homeowner to simply know what the part is called. In 70 years this is the first time I had to deal with a 'top sash guide latch'. I couldn't do a direct google search because I didn't know what I was looking for.

Thanks again...