Poseidon Striker Hop Up Chamber Kit w/ Air Cushion Inner Barrel for Elite Force / UMAREX GLOCK Airsoft Gas Blowback Pistols (Length: 97mm)

"This thing is great shoot straight and hard to about 35-45 yards very impressive over stick
It will not shoot Barrett bbs got them because they was on sell

"I put this in my Elite Force G17 gen 4. Shoots like a laser. Highly recommend over stock.

"Got this for my Umarex Glock 17 Gen4, it fits the stock outer barrel just fine and shoots well. However, I found 2 big caveats to using this.

1. The slide, pulled back and let go, can be sprung all the way off the frame without using the slide release. The effect is more pronounced if you use a stronger recoil spring in your glock. With the magazine in the gun this doesn't happen, so it's a corner case at best.

2. It will not fit the EMG TTI CNC JW2 Combat Master Slide as the included outer barrel is too narrow for this hop up chamber. You WILL need to file down the side of the chamber if you want to use this.

Otherwise, it's a solidly built chamber unit.