Cherne 4" Iron Grip Bypass Plug, 8.7 PSI, ½" Bypass

The Cherne 4" Iron Grip Bypass Plug (part #268-048) is a cast iron mechanical test plug with 1/2" NPT bypass for 4" sewer and drain pipe — the most common residential sewer size. Rated for 8.7 PSI / 20 ft. head pressure. Fits 4" pipe (usage range 3.6"–4.06" ID). At 3.1 lbs and 12.75" long, the cast iron body handles years of field use. Natural rubber O-ring seals round and out-of-round pipes.

Key Features

• Cast iron construction — heavy-duty durability for repeated field use
• 1/2" NPT threaded bypass — controlled flow-through during testing
• 8.7 PSI / 20 ft. head pressure — rated for low-pressure water and air tests
• Natural rubber O-ring — seals round and out-of-round pipes
• Large wing nut design — easy, tool-free installation and superior sealing

Applications

The go-to cast iron bypass plug for 4" residential sewer testing, drain line isolation with controlled flow, and temporary blocking during plumbing repairs. Choose the Iron Grip over ABS plastic grippers when you need the durability of cast iron for repeated field use. Note: 8.7 PSI is the max back pressure for this size.

Questions on sizing or bulk pricing? Call (866) 514-3684 or email us — we ship within the USA and welcome tax-exempt purchasing for qualified accounts.