- The Fluid Extractor is ideal when draining fluid from a reservoir is difficult or not possible. The hose extension can be placed into a reservoir to remove brake fluid, power steering fluid, gear oil, and more. A 7 oz. fluid capacity is applicable to a wide range of applications. Polypropylene construction and double plunger seals to provide durability and help prevent leaking. The tool can also be used in reverse to fill reservoirs with fresh fluid.