12-975XL2 - 1/2" 975XL2 Reduced Pressure Principle Backflow PreventerZurn 12 975XL2 1 2" 975XL2 Reduced Pressure Principle Backflow Preventer The Zurn Wilkins 975XL2 Reduced Pressure Principle Backflow Preventer provides high hazard protection for potable water applications. The wye pattern, bronze body provides separate access to each check valve and the relief valve for servicing. The 1 2" 975XL2 Reduced Pressure Principle Backflow Preventer is used in high health hazard, potable water applications for protection