Don't let a loose hose fitting or valve hand wheel blow an O-ring, or not allow proper valve function to ruin a dive. Not having the proper tools and parts to fix problems can do just that! The serious diver is always prepared to nip a dive aborting problem. That's just two scenarios that this Star Tool can remedy. You ever see non-stainless-steel tools when they have been exposed to salt water environments? Not a pretty sight. It also looks bad when you pull out your rusted open-end steel 9/16 x 11/16 to remove or replace a standard 9/16 or high-flow 11/16 second-stage hose. Many of the new low- profile designed hose fittings may not even allow you to use a standard wrench. The XS Scuba's Star Tool also has a 1/2 and a 5/8 wrench, most common hex wrenches 5/32, 3/16& 1/4 and a valve hand wheel driver. designed for imperial sized products (not metric) this compact sized width 3.85 x 0.5 (9.8 x 1.3 cm) thick (approximately), stainless-steel constructed with silicone over-mold handle tool can be handy when you need it. The Star Tool is a must for a safe-a-dive-kit and makes a great gift for that diving significant other or friend.