Tyre Buff Low Spd Kwk Chng Unoair2300 rpm tyre buffer with hex bit quick change chuck. This unit has a rear exhaust to protect the repair area from contamination during buffing and a safety lock on the trigger to prevent accidental use. By far the most popular style of tyre buffer in the industry. Specs.: 1 2 hp; 2,500 rpm; min. air hose 3 8"; air inlet 1 4" fpt; average air cons. 4 cfm; operating air pressure 90 psi.