'Purified Water' is a pipeline identification flow marker manufactured from a highly durable, self-adhesive polypropylene film, which is then clear laminated. This makes it extremely resistant to scratching, chemicals and solvents as well as extremes of temperature. Our markers have arrow heads at either end to indicate the direction of flow, simply cut off the unneeded arrow and apply the marker to the pipe with the arrow pointing in the direction of the flow.