Free 1-2 Day Shipping | Get up to 2% cashback | Need It Today? Same-Day Delivery Within 50 Miles

Open Box Atomic Aquatics M1 2nd Stage only, 32" hose, Gray

Atomic  |  SKU: AT-02-0100-3P-S+VG
Refer & Earn

Sold out
Sale
⚠️ FINAL SALE - NO REFUNDS
$295.99 $479.95
Shipping calculated at checkout.

Condition

Pick accessories — 90% off with your $250+ order

and your picks are free.

 

Start  $501 pick $1252 picks

  • DiveCatalog Moldable Mouthpiece w/ installation for Regulators

    $34.95$3.50

    1

  • DiveCatalog.com Upside Down Drysuit Hanger w/ Regulator and Accessory Hooks

    $29.95$3.00

    1

  • DiveCatalog.com Universal Dive Gear Hanger with Accessory Arms fits Wetsuits, Drysuits, BCDs, Backpacks

    $29.95$3.00

    1

  • DiveCatalog.com Small Retractor

    $24.95$2.50

    1

  • DiveCatalog.com Heavy Duty Wetsuit and Drysuit Hanger with Extra Wide Shoulder Saver

    $22.95$2.30

    1

90% off applies automatically at checkout on orders of $250+ — or free for signed-in members. Not combinable with discount codes.

Condition Note

May be missing original packaging and minor blemishes (not noticeable after 1-2 dives). This product does not carry a valid manufacturer warranty.

Product Conditions

  • Open Box: Generally unused, returned from a customer, with minor blemishes that are not noticeable. Original packaging may be damaged or missing.
  • Like New: May be slightly used but looks almost new, with minor blemishes that are not noticeable. Original packaging may be damaged or missing.
  • Very Good: Shows signs of use with a few more blemishes. Original packaging may be damaged or missing.
  • Good: Shows more signs of use with noticeable blemishes. Original packaging may be damaged or missing.
  • Acceptable: Heavily used with more blemishes. Original packaging may be damaged or missing.

Payment & Security

Payment methods

  • Amazon
  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Product Information

The M1 Second-Stage is a balanced linear flow design for extremely easy breathing at all depths and dive conditions. The M1 is designed for cold water diving featuring thermal heat sink and improved super-dry exhaust valve. The M1 Second-Stage is built-to-last with a Zirconium plated brass demand valve body, titanium lever and sealing orifice. The diaphragm is made from high quality silicone rubber. This pneumatically balanced poppet second stage has Atomics patented seat saving dynamic orifice which unlike most second stage orifices is a floating valve design which reduces wear on the second stage poppet seat when the regulator is not pressurized adding Life to this important seal.

⚠️ WARNING: This product contains chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.

Frequently Asked Questions

What hose length does the Atomic Aquatics M1 second stage come with?

This M1 second stage ships with a 32-inch hose, is finished in gray, and includes a Comfort Swivel.

How often does the Atomic M1 second stage need to be serviced?

Atomic Aquatics specifies a service interval of 2 years or 300 dives for the M1 regulator line. Routine servicing keeps the balanced poppet and AFC flow control performing as designed.

What warranty covers the Atomic Aquatics M1 second stage?

Atomic Aquatics backs the M1 with limited lifetime coverage on metal parts against corrosion, plus a 2-year warranty on other components. Coverage requires returning the warranty registration card within 30 days of purchase.

Is the Atomic M1 second stage built for cold-water diving?

Yes. The M1 second stage includes a thermal heat sink and a super-dry exhaust valve, both built for cold-water performance. These components are part of the second stage's design to support smooth breathing as water temperature drops.