EasyPro™ Membrane DiffusersMD3 10. 5"diameter Replacement Membrane Diffuser Membrane Diffusers A great alternative to air stones in many aeration applications Hundreds of I slots that open as air pressure builds inside of the diffuser Center of the membrane does not have slots and acts as a check valve when air flow stops Diffusers have a 3 4 male thread inlet and are 10 1 2 in diameter Heavy duty membrane will last for years Uniform bubble distribution with up to 3 CFM air flow