Single Row bearings have internal raceways that are effectively opposite each other, they are designed to accommodate both axial and radial loads and when used in pairs have a tremendous load bearing capacity. Single Row bearings are designed for rigid, high speed, high tolerance applications. Spindle bearings used in pairs in a 'back to back' or 'face to face' arrangement can support axial forces on both directions and moments. Bearings in a tandem arrangement can only support axial loads in one direction. Spindle bearings are available with a 15 degree or 25 degree contact angle.