The R2-series Astromech Droid is a popular line of astromech droids designed to fit in the droid socket of any starfighter. It is commonly designed with a domed or tapered code head, with a cylindrical core in addition to a base, retractable tread leg and two main legs. It has multiple appendages and attachments within its compartments, such as shock prods, welding torches, and is equipped with a holoprojector and a periscope that has a probe function which is usable in space.