The Drain Stopper 100mm x 12.5mm is a heavy-duty mechanical expansion plug designed for sealing, isolating, and pressure-testing drainage pipes, sewers, and plumbing networks.
 
Constructed with a durable metal or high-impact frame and a resilient rubber compression ring, this stopper features a central locking wing nut. When tightened, it draws the outer plates together, expanding the rubber seal outward to form a secure, watertight and airtight grip against the interior walls of the pipe.
 
Specifications:
 
Dimensions: 100mm (4-inch) nominal diameter (fits internal pipe operating ranges approx. 94mm – 110mm)
Outlet Size: 12.5mm (1/2-inch BSP) central threaded outlet or stem
Finish: Zinc-Plated / Galvanised Steel with a black or red heavy-duty rubber seal
Material: Heavy-duty steel or aluminum core with an expandable synthetic rubber gasket
Design Profile: Circular expansion plug with a central locking wing nut and a hollow threaded stem for test hose or pressure gauge attachment
Fixing Type: Internal pipe insertion tightened manually via the central wing nut to expand the seal against the inner pipe bore
Recommended Applications: Air and water pressure testing of new drainage systems, temporary or permanent pipe closures, sealing off sewer lines prior to infill, and plumbing maintenance