The Madbull Ultimate 3 in 1 Hop Up Unit. suitable for most M4 & M16 Rifles

F  Features:

·        Facility for LED Tracer unit (sold separately)

·        Chamber lock o-ring to prevent BB’s falling out of the hop unit whenmagazine is removed.

·        Easy adjustment using new design dial for more stable hop up.

·        Comes with Blue 60 degree Shark bucking.