Support & Downloads



For full instructions with pictures explaining the best way to remove and replace the O-ring, please click here.

Shearwater has a 2 year warranty on all products. The warranty lives with the unit, not with the original purchaser. This means that whether you buy your unit from our dealer network or second-hand the warranty will still be effective. Once the warranty period has passed computers should be serviced annually at your nearest service center.

It is unnecessary to register your unit upon purchase. Every Shearwater unit is tracked with a unique serial number.

We are sorry that you are having a problem with your dive computer that can't be resolved with our FAQ’s.  If your dive computer needs some kind of repair, simply email us at to initiate the process.

Please include your name, address and phone number,  description of your problem, your unit model, S/N and Firmware Version.  We’ll get you an RMA number and instructions on how to send your computer in for repair.  Please do not return your computer to us or any of our service centers without an RMA number.

To find your S/N and firmware, turn on your computer (unless it won’t turn on) and from the main screen press the right side button 8-10 times until you see the S/N displayed (lower left) and Firmware (lower right) of the screen.

The NERD is a full featured technical decompression dive computer. If you are familiar with the Shearwater Petrel or Predator, then you will be familiar with the NERD.

The NERD offers the same functionality and mode options as the Petrel or Perdix but does not run the same software version of firmware. You can read the latest firmware updates to the NERD by clicking here. The NERD has a full-color Mini-LCD display with the same resolution as the Petrel.

With the NERD, for the entire dive, you will see depth, time, decompression stops, and PPO2 readings all with a quick glance. Everything you need to know stays within your line of sight.

The NERD image appears 12 feet (4m) away. If your vision is corrected for 12 feet away, then you can read the NERD.

Although the NERD is located very close to your eye, you do not need near-vision correction. That is, bifocals or reading glasses are not needed nor wanted. The NERD’s optics make the screen appear further away than it actually is.

So the answer is maybe. You need to be able to see 12 feet away. Since you should be diving with correction at this range, most divers will be able to use the NERD. Note that a mask with bifocal near vision correction may cause problems with the NERD.

The NERD display appears about the same as a 32” TV would from 12’ away (a 81cm TV from 3.7m for the metrically inclined).

If you have used a Petrel or Predator (both 2.4” displays), the NERD screen appears the same size as if they were held 1 foot (0.3m) away from your eye. Most divers have no problem reading a Petrel or Predator from several feet away, so the NERD is very easy to read.

See our demo videos for real-life views

The NERD is typically placed to one side, either in the lower or upper range of vision, and so only partially blocks one eye.

Your brain does an amazing job of combining the information from your eyes and filling in missing information. As such, when you choose to look at the NERD display you will see it, but it will not seem to block much of your vision when you look away. It almost seems as if you can see through it.

If you only have vision in one eye, then unfortunately the NERD will probably block too much of your vision to be usable.

The NERD has two piezo-electric buttons located on the sides of the eyepiece. Pressing these buttons allows editing settings, changing gases, etc.

The button type and user interface are the same as on the Petrel and Predator dive computers.

The NERD is mounted on an articulating arm that can adjust height, angle, and distance to account for physical differences between different divers.

The arm is easy to adjust without tools, but holds its position once set. During dive entries in high surf, the NERD may get knocked around a little, but is easy to reposition once underwater and things have calmed down.

Yes, the NERD can be used for Open Circuit diving. It has the same OC Trimix decompression capabilities as the Shearwater Petrel.

However, Shearwater Research does not currently provide a standard mount for Open Circuit diving.

The challenge for non-rebreather diving is where to mount the NERD. The rebreather mount can be removed, leaving a simple dovetail mount that can be adapted to other mounting methods.

There are two issues for compatibility: Mounting and PPO2 monitoring.


Compatible with all rebreathers.

The universal nylon strap mount makes the NERD compatible with every rebreather we have tried.

If you have any questions regarding mounting to a specific rebreather model, contact us and we’ll try to help. Note that other constraints (BOV access, other HUDs, etc.) should be considered when choosing a mounting position for the NERD.

If you don’t like our mounting strap, it detaches leaving a simple dovetail mount for customized solutions.

PPO2 Monitoring:

The NERD has two modes of operation for rebreather divers.

    1.  Internal PPO2 – constant setpoint

In this mode the NERD assumes the rebreather is maintaining setpoint at a user selectable level (e.g. 0.7 or 1.3 ata).

All rebreathers that run fixed setpoints (most closed circuit models) are compatible with this mode.

    1.  External PPO2 monitoring

This is where the NERD really shines. Having PPO2 values from 3 oxygen cells displayed in your vision for the entire dive is a great safety advancement. Always know your PPO2.

The NERD is sold with the standard 7-pin Fischer connector (103 size) for connection to oxygen cells. Any rebreather (closed or semi-closed circuit)   that uses compatible O2 cells and can use a cable with Fischer connector is compatible with this mode of operation.

No, there is not currently an Air Integrated (AI) model.

To purchase the VPM-B upgrade you can contact any dealer from our dealer network, provide them with your serial number, and request to purchase the unlock code.

We recommend you remove alkaline batteries from your unit if you intend to store it for an extended period. Alkaline batteries have a tendency to leak when they have fully discharged.

The name of the o-ring used is AS568-112. The size of this o-ring is 1/2" ID by 3/32" width. This is the same o-ring used in the majority of DIN regulators (not Apeks however).

You can use replacement o-rings made of either nitrile, EPDM, silicone or viton. Be sure to use a lubricant compatible with the o-ring material selected. We recommend a Shore 70A durometer, however both harder and softer will work.

Please see our troubleshooting section here.

To improve the sealing performance and O-ring life span, the battery compartment O-ring gland design has been changed from a crushed gland to a radial gland. Identification of the new radial cap can be made by reading this article. All units being shipped from our factory currently have a radial battery cap.

Firmware Updates

Current Firmware Version: V10

Update instructions

Note: Updating the firmware will reset the decompression tissue loading.

  1. Ensure that you have the latest Shearwater Desktop installed
  2. In Shearwater Desktop, go to Dive Computer > Update Firmware...
  3. On your Perdix, navigate to Start Bluetooth or  System Setup > System Setup > Load Upgrade, depending on your firmware version
  4. Shearwater Desktop will detect your Perdix and select the latest available firmware.
  5. Follow the instructions in Shearwater Desktop to select your firmware language and begin the update.

Getting Firmware Files

The easiest way to update your firmware is to download the new Shearwater Desktop and select Dive Computer-> Update Dive computer.  Follow the instructions on the screen and Shearwater Desktop will handle the rest.

Support Request


  • For repairs, please contact your nearest Repair Center listed below via email or fill out this form for RMA shipping details
  • For cloud software, bluetooth connectivity and IT support inquiries, please email
  • For sales & customer support inquiries, please contact your nearest regional sales representative office.

United States Sales & Customer Support

Curt McNamee
Everett, WA, USA

Canada and California Sales & Customer Support

Alex Tayler
Richmond, Canada

US Repair Center

DIVE-Tronix, LLC
Richard Morton
Snohomish, WA, USA

UK Repair Center

Narked at 90 Ltd
Northamptonshire, UK

Asia Pacific Repair Center

Rob Edward
+64 21 535378
Wellington, NZ

New Zealand Sales & Customer Support

Andrew Simpson
021 2338763

Scandinavian & Baltic Sales

Rannva Joermundsson
+44 (0)7498 067388
Cornwall, United Kingdom