Elite Force Airsoft Gas Gun Rebuild Kit (Model: HK UMP)

"This kit doesn't have the piston recoil guide and spring pictured on the product page for the Glock 17/19 VFC version. I'm guessing that they upgraded the blowback nozzle and housing to the latest G18CV2 blockback version in their lineup and so had it reflected in this rebuild kit. If you're looking for the piston recoil guide, you will have to buy it separately (https://www.evike.com/products/87384/)

Otherwise, it's a perfect replacement kit for the latest EF Glock17 Gen 4 that I have.

"I got this kit for the KWA mp7. Out of the kit I used the return springs, hopup, gasket, and flute valve. This pretty much restored a broken gun back to out of the box performance. Solid kit!

"I got this rebuild kit to replace the broken internal hammer and ended up using the whole kit since the other parts would break eventually. The end result was a working gas blowback pistol!