"Alumina" air stones - three times stronger than white silica air stones! Produces a finer bubble with no increase in pressure.
Inlet fittings are set into the body of the diffuser, making them much less likely to break or twist loose.
Higher density means self weighting.
Cleanable with muriatic acid or chlorine.
More resistant to ozone.
Creates finer bubbles for increased aeration efficiency with no increase in pressure.