Oatey 50193 Acid Core Wire Solder, 0.5 Lb Carded, Solid, Gray, 1/2 lb 40/60 alloy of 40% tin and 60% lead 50/50 alloy of 50% tin and 50% lead 361 General purpose solder for sheet metal work, auto radiator repair and steel gutters 40/60 solders are 40% tin - 60% lead 50/50 solder is 50% tin - 50% lead Contains lead - can not be used on drinking water lines Acid flux is contained in the wire core; no external flux is needed