The Austworld Chrome Plated Hose Tap Vacuum Breaker is designed yo help safeguard potable water systems by preventing back siphonage at hose tap outlets. Suitable for use in drinking water installations. Watermark approved and tested an accordance with AS/NZS 3718. Maximum operating pressure of 1400 kPa and can operate within temperatures ranging from 1?C to 75?C. Internal components include EPDM seals, stainless steel pring and a copper valve. The 15mm model is fitted with 3/4" thread connections and the 20mm model is fitted with 1" thread connections.