Tool has integrated collet with 1/4" Collet Insert (01497). Optional 52898 Thread Guard allows easy access to collet cap. With Thread Guard in place, larger diameter accessories may be run by tool. (All accessories must have maximum operating speed of 25,000 RPM). High-efficiency rotary vane air motor models are ideal for precision deburring and finishing on a variety of surfaces. An ideal tool for use in casting houses, effective on cast parts of aluminum, bronze and brass. Quickly and efficiently removes gates and parting lines in cast parts. Adjustable tool speed from 5,000 RPM to 25,000 RPM. Operate tool and adjust speed by simply rotating rear black cover. Tactile grip on shaft end allows fingertip control, and alerts operator to rotating collet area. Changing of attachment is achieved with easy, two-wrench maneuver. Unique housing shape allows tool to be held as a traditional Die Grinder.