The Profense PF 50 is a 12.7 mm electrically driven (non gas-operated) chain gun produced by Profense LLC, with a maximum rate of fire of 650 rpm.
This weapon is very similar to the M2HB machine gun, however it differs in operation system.
It works with an electric motor as on the Bushmaster gun produced by ATK.
[1] The Profense PF 50 features a digital, programmable, variable rate Gun Control Unit (GCU).
It can also be configured to single shot sniper mode, with optical sight mount.