The Billet buggy brake reservoir threads into a standard 211611011J master. The Billet Brake Reservoir prevents brake fluid leaks by remote mounted fluid reservoirs. The less connections the better, especially in off road cars like the VW dune buggy and sand rails. Plastic reservoirs do crack and leak. So all metal ones are more reliable for this application. The Billet Brake Reservoir will last much longer than the plastic thread in style reservoir.
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