The Cherne 3-1/2" Clean-Out Gripper (part #270-138) fills a gap in NPT cleanout sizing that most plug manufacturers skip. Rated for 17 PSI / 40 ft. head pressure. Fits 3-1/2" NPT cleanout fittings (usage range 3.75"–4.25") — a hard-to-find size common in older cast iron buildings. Glass-reinforced ABS body with natural rubber threaded O-ring and stainless steel hardware. At 7.5 oz it’s a carry-anywhere field tool.

Key Features

NPT-threaded design — guaranteed to seal most damaged cleanout threads
Stainless steel hardware — corrosion-resistant for permanent installations
17 PSI / 40 ft. head pressure — rated for DWV testing
Mechanical wing nut expansion — no inflation, no tools required
Natural rubber O-ring — reliable seal on round and out-of-round surfaces

Technical Specifications

Cherne Part Number	270-138
Nominal Pipe Size	3-1/2"
Usage Range	3.75–4.25"
Max Back Pressure	17 PSI
Max Head Pressure	40 ft.
Body Material	Glass-reinforced ABS plastic
Seal	Natural rubber threaded O-ring
Hardware	Stainless steel
Operating Temperature	0°F to 125°F
Length	2.2"
Weight	7.5 oz
Pipe Compatibility	NPT threaded cleanout openings (cast iron, DWV)
Color	Black

Applications

The 3-1/2" NPT cleanout is common in older buildings and commercial cast iron plumbing but hard to find plugs for. This Clean-Out Gripper seals worn or damaged 3-1/2" threads for DWV testing, inspections, and permanent closure — no need to replace the entire fitting.

Questions on sizing or bulk pricing? Call (866) 514-3684 or email us — same-day shipping on in-stock items, tax-exempt purchasing for qualified accounts.

Cherne® 3-1/2" Tapón de Agarre® Clean-Out