A Strongarm's turret.

A revolver turret is part of a revolver-style blaster. It is a five or six shot cylinder that can drop out of the barrel for easy loading, via a switch. Most modders who do mods on revolver-style blasters make the turret drop down all the way, as well as fit the blaster with more than one turret for more ammunition capacity. X-Shot has done a blaster similar to this called the Xcess, which bears resemblance to a Maverick REV-6 with two turrets.
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