This is an assembly kit of a space exploration vehicle or other non-fictional mechanism.
This eight-legged crab is part of the super-fun Hex Bug line of robot toys (linked below) from Bandai! It's about 4.5cm long, 8cm wide (measured from toe to toe), and about 4cm tall. Powered by two (included) replaceable button-cell batteries (AG13/LR44 type), the crab will move in a straight line (sideways, since that's how crabs move); a loud noise, such as sharply clapped hands, will make it change direction (it also changes directions at pre-set intervals). If it finds a dark place, it'll go into motionless hiding mode; another loud noise or a light source will set it into motion again. A great toy for kids (or small pets!), and a fun gift for anyone who's interested in robotics! Please note that the photos shown are of a prototype; the production version may vary. Also, figures such as this are mass produced and as a result some inconsistencies in finish and painting may occur; these are not considered manufacturer's defects. If you absolutely must have perfection, prepare to do some touch-up work on your own.