1.1/4"/32 mm with 75 mm seal Brass Bottle Traps Chrome plated brass bottle trap. Also available is part number 16198 which is a chrome  200 mm extension tube which includes a wall flange. Meets Current regulations which specify that where waste pipes discharge into a single stack (as is the current 'new build' requirement), the depth of water seal must be at least 75mm (3 inches).