Tightly braided high tenacity Nylon multifilament yarn encapsulates a 99.9% pure lead core. Our "pure" lead construction offers a smaller diameter than standard lead core lines. Color metering every 10 yards with a high visibility dye enables the angler to instantly determine depth. A must for every angler who needs extra weight for deep water trolling. The sink rate of our Lead Core line is affected by many aspects, mainly boat speed, lure weight and current. We do, however, have a simple formula for standard sink rates under a specific condition, which applies to our entire selection of Lead Core lines. When trolling at slow to medium speeds (1.5-2.5mph) using a one-ounce lure in no current; the typical depth will be 6 to 6-1/2 feet of depth per color or 1.25 feet per 2 yards of line. This depth will be effected either up or down by .25 feet for every 1/4 ounce of lure weight. The depth does not vary greatly between pound tests due to the line drag created by the larger pount test lines.