X2=(C-SKF)=15° Contact Angle. TA=One Piece Outer Ring Centred Machined Laminated Phenolic. UM=GB (SKF)=BEARING FOR PAIRED MOUNTING IN RANDOM ORDER; WHEN ARRANGED BACK-TO-BACK OR FACE-TO-FACE THERE WILL BE A MEDIUM PRELOAD. EP7=(P4-SKF)=Extra Pre