Safe-Flo HVE Valves are designed with a unique, one-way valve to provide a physical barrier that prevents the backflow as described in the CDC’s warning on saliva ejectors. The one-way valve closes when the suction is blocked or restricted to prevent the risk of cross-contamination from backflow. The integrity of suction and performance of the HVE tip is not affected, so there is no need to change how you work in order to protect your patients. Use with your favorite HVE tip brand.