This is a stop for the Festool MFT/3 rail guide. It has a foldable stop so that multiple stops can be set up and used on the same rail.
The block is assembled with two M6x20 bolts, two M6 nuts and a washer.
It is better to use a locknut (with a nylon insert) to secure the steel bar or it will get loose as you fold/unfold it.
Sold as a set including 1 spare flag.
The flag in the pictures is made from steel, the ones you will receive are plastic like the rest of the parts.