||I have purchased 3 of these
The work great!! this is the best M4 hop up I have found. I like this better htan the Madbull Ultimate Hop up.
- Fits nicely in metal body M4s
- Gears fit nicely together
- O-Rings help with air seal
If your looking to replace your5 M4 hop up, look no further. try this one. !!
Rating: [5 of 5 Stars!]