Thick line rises and falls due to underwater currents causing fish to strike. User friendly wire that sinks like copper 45lb Diameter = 0.036" Sinks 20' down for every 100' out. Depth Chart for Torpedo Weighted Steel 30lb Diameter = 0.031" Sinks 18' down for every 100' out. Don't forget to pick up a Torpedo Weighted Steel Termination Kit. Looking for a Bulk Spool Need the Torpedo Roller Guide Tip? Catch more fish with Torpedo Weighted Steel