Scuba divers should always check their nitrox mixture prior to diving and plan the dive accordingly!  Don't rely on someone else to check your air supply and simply "trust" that they did it correctly and gave you the correct mix.

• Analox O2EII, Portable Nitrox Checker
• Range 0-100%
• Fitted with digital display, on /freeze display button and a push on flow restrictor.
• Supplied with wrist lanyard and an O2 compensation chart.