Dixon Air King AWR4 Air Hose Black Natural Rubber Washer, 1-5/16" Diameter (Pack of 50) For use with sizes 3/8" to 1" two-lug Dixon Air King couplers and hose ends (not included) Black natural rubber for flexibility Maximum air pressure of 150 psi at 70 degrees F Operating temperature range of -20 to +160 degree F 1-5/16" outside diameter, 1-1/16" inside diameter