- "Installed motor assists in round cycling, converting the MK221 into a fully automatic weapon."
- ―Motorized Cycling Mechanism description (from Aliens: Colonial Marines - Arsenal Upgrades - MK221 Tactical Shotgun - Motorized Cycling Mechanism)
The Motorized Cycling Mechanism
is an motor assisting in round cycling for the MK221 Tactical Shotgun
which converts the MK221 into a fully automatic shotgun.