Robline Tapered Opti Mainsheet [MT-OPTI]Tapered Opti Mainsheet Robeline's tapered lines feature outstanding properties such as excellent abrasion resistance, extra low stretch, and the use of top quality polyester. A specialized line, the Opti (Optimist) mainsheet is double tapered (thinner at the ends, thicker in the center) which provides a better grip. The smaller line diameter at the ends reduces friction in blocks and sheaves. Constructed of a mix of Dyneema with a PA PES (polyamide