All rollers are made of a fine-grained hard wood and treated with teng oil for durability. All RS, RM, and RL rollers fit into the same handle, RH-1, and can be easily and quickly changed out for a roller with a different design or width. Both sizes of the Mini Rollers fit the same small handle, RH-2, and can also quickly be changed out for a roller with a different Mini Roller design.