Semperfli developed Spyder Thread aimed at the traditional market where fine threads like Gordon Griffiths CobWeb are used. Spyder Thread is a color-fast, semi-translucent, unwaxed two twist polyester based fly tying thread in size 18/0 (30 Denier). This thread has a 15% stretch and a breaking strain of 14oz (400g). This allows Spyder thread to lay flat on the hook and, as a semi-translucent thread, it will appear to be natural color for wet, dry and nymph flies. 240 yards (220m) per spool.