Oatey 40501 Hercules Duck Butter Use to lubricate pipe joints Suitable for use on pipes with rubber, synthetic rubber and plastic gaskets Compatible with Copper pipe Certified to ANSI/NSF 61 Use to lubricate pipe joints Compatible with Copper pipe Certified to ANSI/NSF 61 All products are backed with the highest quality technical and customer support programs in the industry All products are backed with the highest quality technical and customer support programs in the industry Water soluble pipe lubricant Adheres to wet and dry surfaces