Tideflex Technologies” Tideflex TF-1 Check Valve features as bill that is formed into a curve that returns to a closed position every time, achieving the tightest possible seal for backflow operations, particularly at low flowrates. The eccentric, flat-bottom design allows installation where the invert of the pipe is close to the floor. The stronger engineered spine provides long-term performance while handling water weight. The valve is designed to provide maintenance-free backflow prevention.