I loved the hardware and has worked well to lock the window but...........................
The included screws are "self tapping". The tip of each screw has a cutter to develope the hole for the screw to go in. There is the problem. The cutting head is too wide and leaves little material for the screw threads to actually grip. Attached to an aluminum frame the first screw barely gripped enough to be firm at all. Changed to a normal screw and now the remaining assembly is snug and tight.