The 4 in. Snap Tee Coupling is designed to join 4 in. single-wall corrugated polyethylene drainage pipes. The coupling snaps on for an easy connection. High-density polyethylene construction; Designed to join 4 in. single-wall corrugated polyethylene drainage pipes; Snaps on easily for a fast connection; Makes a fast, leak resistant joint; Resists corrosion and abrasion; Durable construction