Fend-all Sperian 70 ounce Saline Concentrate eyewash Solution is mixed with clean, potable water in the ratio of 10 : 1 to create preserved, buffered and physiologically correct saline solution. The station must be cleaned to remove contamination from the station walls before refilling the solution. Concentrate solution renders a constant fluid flow rate and Stream height for the entire 15 min of flushing period when used with Porta Stream II and III. 30 months of shelf life when unopened/6 months once opened from date of manufacture.