"I just bought this to replace the broken hop up unit in my m16. For some reason, it shakes inside my gun whenever i fire it, causing my mag to vibrate back and forth a lot. not a big prob for me cause im about to replace my gun anyways.
For a replacement hop up unit, i would recommend this for the price
If u want to upgrade your hop up, i wouldnt recommend this, since u can spend alittle bit more for a better hop up unit"