The AC25 is the third generation of Cressi's IP adjustable balanced piston first stage. It features 2 high-pressure ports and 5 low-pressure ports. 4 low-pressure ports are located on a rotating turret that ensures that regulator and instrument connections are always in the right position. The fifth port is a co-axial Hi-Flow port and is located at the top of the turret. The rotating turret swivels on 360° axis and features 5 low-pressure ports designed to allow the use of more connections without interfering between them. It features the external direct IP adjustment system that can be set using a simple Allen key. The hi-flow conic shape filter is the same for INT and DIN. The spring and the spring bush are coated preventing rust. Its technologically advanced design delivers consistent intermediate pressure and high performance even with low tank pressures. The AC25m it features a matte finish, in gun metal-coated brass. It is combined with the Master Cromo, the pneumatic balanced 2nd stage that features an elliptical shape and a lateral knob for Venturi adjustment. The stages are connected with the Cressi Safeflex LP Hose, a better performance hose compare to the standard one. The AC25m/Master Cromo is available in DIN and INT version. The performance of the regulator is equal to if not greater than more sophisticated products because it maintains a WOB (Work of Breathing) under 0.78 Joule/liter. The regulator meets the requirements of the last European regulation EN 250:2014 and it is certified for use in water over 10°C (50 F).