The US Coupler AR1.660 is a 1-1/4-inch aluminum reverse threaded coupler (1.660" OD) for SDR HDPE innerduct conduit. The sharp buttress-type threads withstand high pulling loads meeting or exceeding the Bellcore tensile standard of 1,000 lbs. The wide eight-pitch thread angle reduces the number of rotations needed for installation to half compared to competitive couplings. Machined with straight thread and long counterbore lead-in for easy starting. Available in smooth or ribbed exterior wall. Suitable for manhole, direct bury, and aerial applications. Made from 6061-T6 aluminum.