Silver Thread Excalibur is the strongest, most abrasion-resistant copolymer line on the market, period! If you’re looking for a line to withstand the punishment big fish can dish out in heavy cover, this line is it. Developed by polymerizing multiple nylon monomers, Silver Thread Excalibur is stronger and more stable. Plus, its diameter is consistent throughout the entire spool. What does this mean to you? Better quality, innovative technology and the best heavy-duty fishing line available. Each spool comes with an elastic line-keeper. Keep this keeper on the unused portion of the line while on the spool to protect it from harmful light rays. You can also use the keeper to assist in winding unused line back onto the spool. Poke the line through the keeper just behind the pull tab, then pull the pull tab around the spool to wind the line back on.