The Devastator "Executive Edition" Shotgun is a special edition of the size 3 Devastator Shotgun made by Kastak Arms. It has a twelve round capacity magazine (the in game information lists the ammo capacity incorrectly as 20 rounds), it can be modified with size 1 optics and size 3 barrel attachments and size 2 underbarrel attachments.
“
Kastak Arms 'Devastator' is a pump-action plasma shotgun capable of delivering sustained medium range, high-impact plasma blasts for close combat, room clearance and other combat operations. If the situation requires a high-power presence, look no further than the Devastator.