The Modify M4 hop up chamber is one of the first innovative M16 hop up designs in a long time. The geared hop up adjustment arm and built in nub make this hop up unit one of the most consistent designs for any M4 or M16 airsoft rifle.
Modify's chamber features a host of new improvements, including bearing sleeves on all the adjustment dials, and retention o-rings to keep the dials tight. An o-ring under the main knob keeps it from self-adjusting, so your hop up stays where you put it. Instead of the traditional spring tension and cam design, the new Modify M4 hop up unit uses a gear rack to precisely align the hop pressure arm. This eliminates any bounce, giving more consistent pressure against the bucking. Additionally, a spacer is included to allow for adjustment in a wide range of AEG manufacturers.
The Modify M4 hopup chamber will fit any M4 airsoft AEG with a one-piece hop-up unit design, including Classic Army, G&G, SOCOM Gear, and other M4 and M16 AEGs. The precision construction of the Modify unit, along with the adjustment spacer, make it one of the most versatile hop-up units ever. In some cases, this unit will be compatible with more mags and enhance feeding reliability over the original hop-up unit.