Double check valves can be mounted Indoors or out. They are not approved for use with In-line fertilizer systems. Designed for protection of the potable water supply in accordance with national plumbing codes. For non-health cross connections and continuous pressure applications. Standardly furnished with ball type test cocks and quarter-turn full port resilient seated bronze ball valve shut-offs. 3/4" and 1 " shut-offs have tee handles. Supply pressure up to 175 PSI. Water temps. to 140?F constant and 180?F intermittent (3/4" - 2") and 110?F constant, 140?F intermittent (2?" and 3").