The ARAK is part AR and part AK. The AR part is that it's made to work with AR-15 lowers, but the upper is built around a long-stroke gas piston system like those used in Kalashnikov rifles. It also draws from the FAL deck with the type of adjustable gas regulator it uses. Another AK-like feature is that the bolt carrier runs on hardened steel rails inserted into the upper receiver.
FNH PS90 SBR. Custom Midnight Snakeskin duracoat paint job. U.S. Secret Service as well as many SWAT teams around the world have the fully automatic P90 in service. This firearm is regarded as one of the best in the world.