Tusa RS-790 Regulator


2 in stock



The R-700 is a balanced diaphragm first stage designed for cold-water use, it features a dry ambient pressure chamber that prevents water contact with the diaphragm maximizing performance in temperate water conditions below 50°F/10°C.  Additionally, the R-700 has an external rib section that nearly doubles the surface area for thermal exchange further reducing ice formaton that can lead to freeze up in extreme conditions.  The R-700 has two high pressure ports and four low pressure ports including two high flow (HF) that deliver up to a 15% increase in air flow.  It is available in both INT (yoke) and DIN versions.

The S-90 second stage is a compact pneumatically balanced system that features a composite housing which insulates and protects under extreme cold-water conditions.  The S-90 is equipped with a built-in venturi adjustment lever allowing the diver to select a surface or minimum setting reducing possible free flow or a dive setting for maximum air flow during the dive.

The RS-790 offers the following features:

Key Features

  • First Stage:
  • Balanced Diaphragm Design
  • Anti-Freeze System
  • Dry Ambient Pressure Chamber
  • Ideal for Temperatures Below 50 Degrees Fahrenheit (10 Degrees Celsius)
  • Nitrox Compatible to 40%
  • Environmentally Sealed
  • 2 High Flow LP Ports 15% Increase Air Flow
  • 2 Standard LP Ports
  • 2 HP Ports


  • Second Stage:
  • Pneumatically Balanced Design
  • Lightweight, Compact Composite Case
  • Venturi Adjustment Lever
  • Ortho-Consciously Designed Silicone Mouthpiece
  • Owner’s Manual
  • Limited Lifetime Warranty

Additional information

Weight 2 kg
Dimensions 40 × 20 × 20 cm