GF Piping Systems PVC Pipe Fitting, Coupling, Schedule 80, Gray, 3" Slip Socket Coupling for connecting two pipes with the same diameter in a straight run Socket openings on both ends for connecting two male pipes PVC for chemical and corrosion resistance, high strength, and less weight than fittings made from metal Operating temperature range of 0 to 60 degrees C (32 to 140 degrees F) Meets ASTM D1784 and D1785 standards for quality assurance, and meets NSF standards 14 for plastic piping and 61 for potable water service