Madbull Upgraded Cylinder Set - Standard Version for SIG550 Net-Weight-(g)_1122 At first glance it looks

At first glance it looks like one of those Patriot M4 pistols with free float rails

Suitable for KJ Works M4A1 Series Airsoft Gas Blow Back GBB Rifle (Tanio Koba)

Improved Ergonomics Grip Housing Design can withstand the toughest combat weapon application

5-10x40E-SF(Red/Green Reticle)

Madbull Upgraded Cylinder Set - Standard Version for SIG550 Net-Weight-(g)_1122 At first glance it looksThe Madbull Standard Cylinder Set has all the necessary parts to upgrade or replace the cylinder assembly in your gearbox. The Cylinder Set includes a cylinder head, air seal nozzle, Madbull Alien green PX piston, the cylinder, and a polycarbonate mushroom piston head w bearings. The Cylinder set is compatible with most major brands of AEG. Take your standard gearbox to the next level of performance with the Madbull upgraded cylinder set. It is a must