Ensure your plumbing pipe joints are strong and well fused with Weld-On Plumbing PVC/CPVC Primer. Compatible with all schedules, sizes, and classes of PVC and CPVC pipes and fittings, this PVC/CPVC cement primer helps ensure that every joint you weld is properly fused. Once applied, it acts quickly to soften the joining surfaces, helping to promote maximum fusion during welding. Follow with the plumbing solvent cement of your choice to achieve a strong, high-contact, and long-lasting joint.