The flexible Tophats pipe connector is available in 110mm, 160mm and 225mm.The tophat connector is used for connecting inlet, outlet and vent pipes through impermeable membrane liners. These will then be joined to the membrane using a 50mm double sided tape between the top hat and membrane, a 75mm tape should then be used around the perimeter of the top hat.These tophats are to be used as part of an attenuation or infiltration systems where pipes enter the crate to create sustainable urban drainage solutions (SUDS).Please allow 2 - 3 days for delivery of this product.