Cycle With Style Hydraulic Brake Bleeder - Makes Bleeding Your Brakes a One Person Job Easy To Use - Makes bleeding your brakes a one-person job. Usage - Aids in the bleeding and servicing of hydraulic brakes. Check Valve - The unique check valve allows fluid and air to escape while preventing air from re-entering the system. Note: This tool requires priming and will not bleed air from a dry system. Satisfaction - Your satisfaction is guaranteed or your money back!