Masterline 8 Loop MainlineMasterline 8 Loop Mainline The Masterline 8 Loop Mainline is a course friendly water ski mainline built from 80 strand Poly P rope at 70' total length. Eight take off sections cover the line lengths most recreational and club level course skiers run, with shortenings from 15' off through to 39. 5' off. The 80 strand construction sits one tier above the 60 strand 5 loop, holding shape and section accuracy better under repeated tournament style course