The UCH21 top charging handle for all Glock 20, 21, 30, 40 generations is the easiest way to charge your Glock without having to modify your pistol (only compatible with OEM Glock slides). Installation is easy and can be fitted to your Glock in under 2 minutes using the included hardware and tool. Comes with a high profile charging handle top, a low profile charging handle top, and a base.