The basic Grid-Lign coupling consists of two steel shaft hubs, a high strength spring steel tapered grid element, two seals and a cover assembly. Misalignment and end float are accommodated by the sliding action of the grid in the lubricated hub grooves. Dodge Grid Coupling Hub, Type T10/T20, 1020T Coupling, 7/8 in Bore Dia, 1.56 in Hub Dia, 3/16 x 3/32 in Keyway, 3600 rpm Maximum, 1.9 in Length Through Bore, Steel