Length between perpendiculars
Length between perpendiculars (often abbreviated as p/p, p.p., pp, LPP, LBP or Length BPP) is the length of a ship along the waterline from the forward surface of the stem, or main bow perpendicular member, to the after surface of the sternpost, or main stern perpendicular member. When there is no sternpost, the centerline axis of the rudder stock is used as the aft end of the length between perpendiculars.