Arlecchino wears a belt and a slapstick.
You might have heard of "slapstick comedy," which is named after this prop.
A slapstick is made out of two thin strips of wood separated at the handle
by a half an inch or so. When the slapstick hits an object, the two
strips of wood slap against each other to make a loud sound, without
hurting the person being hit.