Edelbrock/Russell 639520 Speed Bleeder
The Edelbrock/Russell Speed Bleeder replaces the original bleeder valves in calipers and wheel cylinders with a spring-loaded one-way ball and check valve design.  This unique check ball design opens to allow the old fluid and air out and closes automatically between the pumps preventing the old fluid and air from re-entering the line.  A special coating on the speed bleeder threads keep it from admitting air into the system and keeps expelled air and fluid out.  The check ball is centerless ground 410 stainless steel which resists corrosion and galling.  It features a patented thread sealing system that displaces air and moisture during thread engagement as well as eliminates air from being pulled back into the system during bleeding.