The XS2/AC2 Regulator is an exceptionally dependable non-balanced flow-by-piston designed 1'st stage regulator that is a great choice as a new diver's rig, or for use as a stage bottle regulator system. The 1'st stage has 1 HP port and 4 LP ports and is made from marine grade chromed brass for long life and durability. A conical filter is used which has greater surface area for higher air flow characteristics through the 1'st stage regulator. The XS2 Compact Second-Stage housing is made of durable non-corrosive hi-tech polymers and has a dependable downstream demand valve mechanism. The flow of air is channeled to the mouthpiece by injection, creating a venturi effect enhancing the performance. The 2'nd stage comes with a flow deviator that acts on the Venturi effect, with dive/pre-dive adjustment function. Regulator comes with a comfortable silicone mouthpiece. The XS2 Compact AC2 Regulator weighs 35 oz (994g) with the hose and comes with an owner's manual. Regulator is certified to EN250/2000 standards and is made in Italy. The XS Octopus is a lightweight, high performance second stage regulator. The XS has a Venturi dive/pre-dive switch which will help control the sensitivity of the regulator when not in use, yet when switched from the pre-dive to dive position the regulators performance will instantly increase. The XS Octopus has a dependable downstream demand valve mechanism for reliable performance. The XS Octopus is equipped with a 33" (84cm) 3/8" threaded hose, has a yellow front cover for easy identification in an out-of-air-emergency. The regulator has a soft and comfortable liquid silicone mouthpiece and the housing is made of durable impact resistant hi-tech polymers. The regulator weighs 7.27 oz (206g) without the hose and 12.7 oz (359g) with the hose. Regulator is certified to Annex B EN 250.2014 standards. Regulator is Italian made.