This is the 1-lb Solder Spool The solder is approximately 1-lb and is strung around a convenient use spool. This solder is composed of 60% tin and 40% lead which allows it to melt at a lower Temperature. It creates a rounded bead of solder. This solder is designed for general electronic use. The 1-lb Solder Spool is the base for any of your cabling projects. For more information on our products, please contact our customer service department at 888-519-9505. For all your cable and connector needs, choose Show Me Cables.