First rate lead wire on standard thread spools. Soft formula. Use them with a regular bobbin holder for effortless fly tying.
Please specify size when ordering. + 0.38mm (small) wt per spool: 20,8 g + 0.63 mm (medium) wt per spool: 27,0 g + 0.76 mm (heavy) wt per spool: 32,8 g + 0.89 mm (extra heavy) wt per spool: 34,5 g