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, 1080T Coupling, 2-1/4 in Bore Dia, 3-1/2 in Hub Dia, 1/2 x 1/4 in Keyway, 3600 rpm Maximum, 4.13 in Length Through Bore, Steel