This is the Dive Rite XT1 1st stage with XT4 2nd stage regulator

Features:

XT1 First Stage

• Material: Black DLC-coated brass.
• Weight (DIN): 1 lb, 15.2 oz (885 g).
• Weight (Yoke): 2 lbs, 6.8 oz (1,100 g).
• Intermediate Pressure: 140 PSI.
• 5 LP ports (3-8/24 UN).
• 2 HP ports each angled 90? from fitting (7/16-20 UNF/ISO 263).

The XT1 First Stage is environmentally sealed to protect against internal corrosion, contaminants, and freezing so you can feel confident diving this regulator in any underwater environment. The XT1 is suitable for oxygen-enriched mixtures if precautions are taken (diver must use oxygen-compatible materials, keep the regulator clean from contaminants during assembly and use, and open the tank valve slowly).

XT4 Second Stage

• Weight: 9.4 oz (266 g).
• Balanced downstream internal second stage valve.
• Second stage adjustment knob fine-tunes inhalation effort.
• Can be oriented for left or right hose routing.
• Oxygen compatible O-rings and lubricant.

This regulator was designed using the Venturi Effect to direct airflow directly from the valve to the mouthpiece, resulting in the smoothest possible inhalation. An ?easy grip? dive/pre-dive switch allows the diver to avoid a free flow at the surface and works well even with gloves. This adjustable design enables the diver to fine-tune their cracking pressure to suit their preferred breathing resistance.

All internal moving parts in the XT4 Second Stage are coated in Teflon and a finned metal heat exchanger is utilized for improved cold-water use. The XT4 is suitable for oxygen-enriched mixtures if precautions are taken (diver must use oxygen-compatible materials, keep the regulator clean from contaminants during assembly and use, and open the tank valve slowly).

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