The Slim Range Is Specially Designed To Be Fitted To The Flattest Trays On The Market. *The Silicon Membrane Guarantees Excellent Flow Rates And Acts As A Vapour Barrier And Air Admittance Valve. *Anti Back Siphoning System. *No Smell Guarantee: The Membrane Replaces The Water Trap. *Easy To Maintain: Top Access Membrane With Removable Hair Filter. *High Performance Flow Rate: 27 L/Min Under 15mm Of Water. *Outlet: 40mm Compression