Called the "Steak Saver" because when the propane tank runs out, the grill can be connected to a 1lb bottle, saving that steak from ruin. Most commonly used with 1lb bottles to grills or distribution posts to grills. Solid brass construction.• For use with propane gas• 1in - 20 Female Throwaway Cylinder Thread x Female P.O.L. and Acme Thread• Most commonly used with 1lb bottles to grills or distribution posts to grills• Has brass nipple to open safety valve in male throwaway cylinders• Has rubber gasket for sealing• Solid brass construction.