Acid Waste Mechanical Joint Lubricant is approved for use with Labline & Plenumline piping systems. When tightening IPEX mechanical joint fittings, the dry fitting surfaces at times may tend to bind against each other. This prevents the union nuts being fully tightened and prevents the ElastoliveTM from properly seating against the fitting sealing area. One or both of these issues can cause joints to leak. To overcome this, IPEX Acid Waste Mechanical Joint Lubricant should be used on both fitting threads and elastolives. The lubricant permits easy take up of the nuts and allows the pipe with the elastolive to glide smoothly into position against the fitting sealing area. The lubricant will enable the union nuts to be tightened to their full thread capacity. Lubricant is highly recommended to be used with Labline piping system.