The CI Range of inch-size fittings is offered for tube sizes 1/4" O.D. and 3/8" O.D. The fittings are manufactured in white acetal, with a food grade EPDM O-ring. They have been developed for the water industry but are equally suitable for other potable liquids. They are also recommended for intermittent hot water applications. The CI Range is NOT suitable for compressed air applications.