A 45° elbow long tangent is a long radius (LR) with the centerline curvature equal to 1-1/2 times the nominal pipe size (NPS) and a straight extension at both ends (long tangent) for 2 inch and larger sizes. Tangent elbows provide a straight length at the end to accept a Slip-on Flange. The tangent end for the flange is not beveled.