Batons are non-lethal melee weapons created to knock a target unconscious. They mostly used by guards and police for riot control and criminal arrests.
The expandable baton is used by peace-keeping and riot-control forces all over the world in 2052. It's composed of a cylindrical outer shaft containing two telescoping inner shaft that lock into each other when expanded. The shafts are made of steel and a few whacks can knock a target unconscious.
The side-handle baton is a heavyweight polyurethane baton with a short side handle at a right angle to the shaft. It's commonly used in 2072 by guards or military personnel (like SSC or WTO) to the detriment of the expandable baton.