Balystik Multi Outer Barrel Kit for Wolverine MTW M4 Legions Imperialis but you can also use

but you can also use this upgrade part with the M4 MWS magazines as well

This may or may not be a requirement depending on your rifle

The plate receiver of the Umarex (Elite Force) Heckler & Koch MP5 is manufactured from stamped steel

Precisely controlled by an Advanced Electronics kit with optical select fire sensor and a Premium FCU

Balystik Multi Outer Barrel Kit for Wolverine MTW M4 Legions Imperialis but you can also useMulti outer barrel for M4 MTW including 3 extensions and one base, extensions can be added together to extend barrel size. Features: Aluminium 6061 CNC machining Included: 1x Outer barrel extension 90mm CCW 1x Outer barrel extension 140mm CCW 1x Outer barrel extension 190mm CCW 1x Outer barrel base 14mm CCW 1 x O ring