Designed for the unattended filling of tanks, reservoirs and sumps in RO units, handy product can be used to automatically fill multiple open reservoir storage tanks. Positive shut-off completely shuts off all waste and product water. Not recommended for evaporation replacement in aquariums. Great for conserving water. Kit includes an ASO valve, stainless steel float, check valve, mini-bladder tank, a straight ball valve, tubing and other necessary fittings. Requires a 9/16 in. mounting hole in tank.