7/8 Long Arm Alloy Steel Hex Key supports the socket-screw system by matching a 7/8 in. width across flats to the working tool. The ASME B18.3 width band is 0.8720-0.8750 in.; the key is held just under nominal so it enters an in-tolerance socket and bears on the flats.
Heavy equipment and large socket cap screws at the upper end call for wider keys that are harder to restock loose. The Long Arm key is the reach-oriented member of the pair, while the Short Arm version fits compact work areas.
For industrial purchasing and maintenance teams, Cold Headers helps match width, series, and catalog identity. Review the 7/8 in. width, Long Arm format, short-leg length, and arm length before ordering. This width is part of the hard-to-find end of the range, where loose-driver restocking is often the real problem.
Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.
