Oatey 30600 Lubricant, For Rubber Gaskets, 32-Ounce Non-toxic, soft, paste like material for lubricating bell joint pipe gaskets. Will not deteriorate natural or synthetic rubber. Will not support bacteria. Dissolves in hot water. Only water soluble tinning flux base that meets ASTM B-813 As thick as No. 5 flux Solder powder added to pre-tin the pipe