The RG-3100S Tec is an adjustable 2nd stage, the pneumatically balanced design gives consistent gas flow at all times.  Featuring a Venturi assist to produce a smooth inhalation, and a dive/pre-dive lever to help avoid free flows on the surface.  All o-rings are Viton, making this 2nd stage suitable for breathing high oxygen percentage gas mixes. 

Featuring an expanded exhalation port, to reduce CO2 buildup while breathing, all metal parts are chrome plated for increased life.  The 3100S Tec is designed for cold water diving, with anti-freeze protection built-in.

The adjustable design allows the diver to fine-tune the breathing pressure of the second stage while in the water, to suit conditions.  The front cover of the 2nd stage is user-changeable and available in 6 different colors (Green, Blue, Purple, Orange, Red, Yellow). 

The RG-3100S Tec comes supplied with a 75cm (29 inches) rubber low-pressure hose with a 3/8"x24 thread; suitable for most modern 1st stages.