This is a fixed-pose model of a science-fiction/anime item.
From the Sideshow Collectibles website:
Sideshow Collectibles proudly presents the newest entry in the Star Wars Legendary Scale bust series, Captain Rex. The esteemed Clone Captain of the 501st is crafted in 1:2 scale, with outstanding attention to detail. Each bust is individually hand painted and finished with the exceptional quality that is the trademark of a Sideshow Collectibles piece.
The Captain Rex Legendary Scale Bust features:
DC-17 Blaster
Moveable Antennae
Product Size: 24" H (609.6mm) x 11.5" W (292.1mm) x 13.5" D (342.9mm)