This item is a set of optional parts for modifying or detailing robot and other science-fiction kits. 13 parts.
Assembly Guide
These crisply molded resin parts are the makings for a super-detailed replacement for the right arm of Bandai's 1/35-scale Guren Nishiki (sold separately). (The photo below shows the parts cleaned up and assembled onto the Mechanic Collection kit; you'll need to do that yourself).