Highland Deluxe Inline Second Stage Shut OffHighland Deluxe Inline Second Stage Shut Off. Features: Install between standard regulator hose and second stage Slide machined Delrin collar to shut off gas flow Commonly used with deco rigs, stage bottles & drysuit inflation Prevent critical gas loss 9 16 18 UNF male inlet to 9 16 18 UNF female outlet threads Low pressure use only below 200 psi WARNING: When shutting off gas supply to the second stage, there must be some other type of over pressure