Expansion Back for Zebra ET50, ET51, ET55 and ET56 tablet computers. The Expansion Back screws onto the back of the tablet and replaces the cover of the tablet's battery. The Expansion features a rotating hand strap that allows the tablet to be held with one hand. In addition, the Expansion Back has a slot for an optional battery that allows you to use the tablet longer.
The optional battery needs to be ordered separately (see Accessories below).