Hollis 221 DC-4 Balanced Regulator, DIN 240.3451.07 033193

Video: Hollis DC4 212 and 221 Balanced Regulators Video Review
Mfg Part #: 240.3451.07
  • For cylinders fitted with a DIN valve only (for cylinders fitted with a standard yoke valve order adapter below)
  • Nitrox compatible to 40% (the recreational limits of nitrox)
  • Over-balanced first stage achieves superior performance by increasing your air flow the deeper you go
  • Designed for extreme depths and cold water
  • Pneumatically balanced second stage 
  • Orthodontic mouthpiece to alleviate jaw fatigue by easing bite needed to hold regulator
  • "Diver Adjustable" venturi to prevent unwanted free-flow
  • FULL MANUFACTURER’S WARRANTY

Customer Reviews for Hollis 221 DC-4 Balanced Regulator, DIN:

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Questions and Answers for Hollis 221 DC-4 Balanced Regulator, DIN:


  • wunson:

    do you have this in YOKE? also, if i buy this and an octo and a gauge, can you guys put everything together and test it before shipping? thanks.

    Bob  (Certified Scuba Instructor at Scuba.com):

    For inventory status or information please contact our instructors at 800-347-2822 (800-34SCUBA) All equipment requiring assembly is put together by one of our certified scuba instructors prior to shipping. Just one of the many benefits of shopping with Scuba.com

221 / DC4
Built with the same quality as the DC1, without the swivel turret, the DC3 is the ideal 1st stage for double cylinder configuration as well as perfect for single cylinders. Paired with the 221 which uses the same technology as the 212 without the dynamic adjustment . This reg set is designed for those who believe keeping it simple is best. Only for DIN valves.

Details Specs
221 Second Stage
Pneumatically balanced second stage
Ergonomic A.V.S. (Adjustable Venturi System) Dive/Pre-Dive Switch
Patented Orthodontic Mouthpiece with High Density Bite Tabs li>
DC3 1st Stage
High performance over-balanced first stage provides progressively greater intermediate pressure as depth and gas density increases for superior gas delivery under the most extreme conditions
Designed to withstand the rigorous CE standard for coldwater performance
Environmental sealing prevents internal corrosion, contaminants, and icing of the first stage

4 low pressure ports
1 high pressure port
Yoke or 300 Bar Din
Nitrox compatible to 40%

Not available for shipment to Australia

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