[1 & 4 Inch Blue]
[3 & 8 Inch Blue]
[1 & 4 by 50 Black]
[3 & 8 by 50 Black]
Hydro Logics reverse osmosis filter tubing in blue. Sold in lengths of 50 feet with an outer dimension of 3/8th inch. Extra tubing can be useful for customizing your indoor hydroponic water filtration system.