The Max M1 motor is built to last and push the limits of your airsoft gun

which necessitates more frequent reloading

Rotary Style Adjustable Hop-up

but will fit on any airsoft gun with a 14mm counter-clockwise thread

Fire Modes: Single shot

MAXX Model Airsoft CNC Aluminum Hop-Up Chamber HPA Series M4P - PRO (Blue) aeg spring guide The Max M1 motor isMaxx Model CNC Aluminum Hopup Chamber M4P Pro (with BB Latching System) unit is precisely machined to perform accurately and consistently with HPA PolarStar Engines on standard M4 M16 platform. The Hopup Chamber M4P unit is built with an aluminum Rotary Dial Knob for fine hopup adjustments, the precision Hopup Lever and 4mm Bucking Nubs (6mm Bucking Nubs are optional) to perform best with R Hop and Standard Hop to keep the BB shooting accurately and