Metal Whisker Magne-Matic CouplerThis industry leading coupler features an all metal coupler head, shank, and Whisker® centering spring and comes complete with insulated draft gearbox and lid. The 147 Magne-Matic® Whisker® Metal Coupler may be mounted with the included 242 Snap-Together Gearbox or with other manufacturers cast-on coupler pockets.It is not recommended to use a metal coupler directly on a metal surface or in a metal draft gearbox to avoid possible electrical crossover and shorting that may cause damage. Use the provided insulated gearbox or insulated 27 coupler.Package Includes:(2) Pair 147 Whisker® Metal Couplers - Medium Underset Shank(2) Pair 242 Snap-Together Gearboxes(2) 622 Knuckle Springs