Allows bleeding master cylinders on or off vehicle. Kit contains plastic adapters in standard or metric sizes, standard: two-3/8”-24, one 7/16”-24, one- 9/16”-18, one-9/16”-20 and two-1/2”-20, metric: four-M10 x 1.0, two-M10 x 1.25, one-M11 x 1.5, two-M12 x 1.0, one M12 x 1.5 and one-M13 x 1.5, hose holder, 20” hose, thread gauge and instructions.