For pricechoose optionsSelect Option 100mm (4in) 200mm (8in) 225mm (9in) 250mm (10in) 300mm (12in) 375mm (15in) 450mm (18in) Quantity Add to Basket Centre locking drain test plugs with steel plates, steel wing nuts and brass blanking caps. Suitable for air or water testing of drains and sewers.