1 1/2 in Steel Undersized Machine Key with Plain Finish/ END ITEM IDENTIFICATION: AIRPORT SURVEILLANCE RADAR 9 (ASR9) SPECIAL FEATURES: USED IN DRIVE UNIT ASSY (GEARBOX/REDUCER) (P/N: 43569-1022) MACHINE KEY, UNDERSIZED, SQUARE END TYPE; 1 3/4 LENGTH, 1/4 IN SQUARE, -0.002 IN THICKNESS TOLERANCE, -0.030 IN LENGTH TOLERANCE, TENSILE STRENGTH 64,000 PSI, ROCKWELL HARDNESS B85, HOLDS PULLEYS AND GEARS ON TRANSMISSION SHAFTS MATERIAL: STEEL OVERALL STYLE DESIGNATOR: B15 PLAIN