Rubber Expansion Plug with Integral Test Valve – Multi-Utility Pipe Stopper.AC Cable Solutions’ rubber duct plugs are engineered to deliver reliable sealing for open-ended ducts and pipes across utilities, telecoms, highways, and rail applications. Designed as reusable mechanical stoppers, they prevent the ingress of water, air, dirt, and vermin – all without the need for messy resins, or expanding foams. Ideal for use on critical infrastructure projects, our duct sealing plugs are trusted for motorway communications networks, underground installations, and above-ground maintenance hubs. Each plug is precision-manufactured from durable, corrosion-resistant HDPE combined with a pressure-rated thermoplastic elastomer, ensuring a long-lasting, watertight barrier that performs in both buried and exposed conditions. All-in-One Sealing SystemEach plug combines a robust HDPE body with an expandable thermoplastic elastomer gasket, creating a watertight and airtight seal up to 0.5 bar, complete with Integrated tie rings for easy pull cord attachment. Wide Range of SizesAvailable for duct IDs from 20mm to 165mm, with metric sizing to suit UK standard ducting systems. Custom solutions can be provided on request for non-standard applications. Reusable and Re-EnterableUnlike foams, resins, or mastics, these plugs can be removed and refitted multiple times without losing performance. They also support future cabling thanks to optional insertable cable grommets—ideal for telecoms, fibre, and data projects. Built for InfrastructureManufactured to strict tolerances, our duct sealing plugs are used nationwide in motorway communication networks, manholes, equipment cabinets, conduit ends, and decommissioned ducts. Resistant to wear, chemicals, and weathering, they provide a durable barrier against water, air, rodents, and debris. Technical Overview Material: HDPE body with thermoplastic elastomer gasket Seal Rating: Airtight and watertight to 0.5 bar Sizes: Duct IDs from 20mm to 165mm