Speed Bleeder Screws allow true one-person brake bleeding with no special equipment and without a compressed air source. When the Speed Bleeder screw is opened, a one-way ball check valve lets air and fluid out, but nothing back in. Speed Bleeders are externally identical to our standard bleeder screws. Some other brands use the seat as the moving part, creating potential leak points. Our Speed Bleeders give you the convenience of a check valve without sacrificing the reliability of a standard bleeder screw.