TUSA RS 790 Regulator

TUSA's RS-790 Regulator. The all chrome plated marine brass first stage regulator is a balanced diaphragm design which is environmentally sealed.

The diaphragm membrane transmits the pressure changes to the internal mechanism eliminating the need for the surrounding water to enter the intricate mechanism.

The benefit of this type of first stage design is that none of the internal parts are exposed to contaminants such as salt, sand, chlorine or pool acids.

These environmental contaminants cause corrosion and mineral deposits to form on the internal mechanism deteriorating regulator performance.

TUSA has taken this concept one step further with the addition of a Dry Ambient Pressure Chamber.

A standard diaphragm first stage regulator allows some water to enter the main spring cavity.

Although the cavity is not associated with the intricate internal components, it does allow the cold water to rest against the primary diaphragm cooling the air that passes through the first stage.

This colder air can promote second stage freeze up when diving in cold water.

The Dry Air Ambient Chamber prevents water contact with the diaphragm and spring maximizing performance, at any depth, in cold water conditions below 10 °C (50 °F).

In addition the outside of this chamber is ribbed increasing the parts surface area thus acting like a radiator to increase heat transfer further reducing the problems associated with cold water diving.

The first stage has two high flow low pressure ports (LP) and two standard LP ports along with two high pressure ports (HP). The high flow LP ports are positioned near the diaphragm and offer up to a 15% increase in air flow.

The S-90 second stage is also a pneumatically balanced system.

A small chamber positioned at the end of the poppet assembly traps air and forces the poppet back against the intermediate pressure orifice.

This provides decreased inhalation resistance and increases smooth breathing in all conditions.

The lightweight compact composite designed second stage is also equipped with a Venturi Adjustment Lever.

This lever has two positions that are selectable by the diver. Use Surface" or minimum setting when entering the water or on the surface, reducing the sensitivity and possible free flow of the second stage. Use the Dive" or maximum setting for maximum air flow during the dive.

The second stage comes standard with an orthodontic-conscious designed silicone mouthpiece.