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Kirby Morgan 77 500-091 Commercial Diving Helmet with Male Waterproof Connector

SKU: 500-091 Rate this product

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Availability: Usually ships 1 weeks after receipt of order

Restrictions / Notifications

  • Reseller Restriction
    Due to vendor restrictions, this item cannot be sold to a reseller. If you are a reseller, please call us at 760-208-6500 or email for more details.

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  • Air Train - The air train diffuses incoming breathing air/gas onto the face port/lens to defog and ventilate.
  • Defogging Steady Flow Valve - Provides an additional flow of gas into the helmet for ventilation and defogging.
  • Emergency (EGS) Valve - Emergency (EGS) Valve supplies backup breathing gas to the diver. This valve is an integral, built in part of the stainless steel sideblock.
  • Gas Supply Non-Return Valve - Commercial Rated™, It prevents loss of gas pressure in the event of umbilical damage.
  • Handle - Removable Grip and handle. Handle can be removed without breaking seals, making it quick and easy to attach accessories.
  • Nose Block Device - Nose Block Device allows the diver to block the nose to equalize ears.
  • Rapid Change Modular Communications Systems - Because the module is easily removed the helmet, repair or replacement of communications parts is quick and trouble free. It is available with either a male waterproof connector or a bare wire post connection.
  • REX® Regulator - Full adjustment balanced piston is a breakthrough design that exceeds all requirements of all government or other testing agencies. It has the best work-of-breathing performance when compared to ANY other commercial diving regulator.
  • Silicone Oral Nasal Mask - Made of a superior silicone material which is hypo-allergenic and has a longer work life than latex.
  • Stainless Steel Shell - After x-ray inspection, each 316 stainless steel shell, is precision CNC machined to tight tolerances, to ensure proper fit to all other mating parts. The shell is durable and easy to maintain. Easily cleaned using a Scotch Brite® or similar type cleaning pad.
  • Stainless Steel Side Block - Multi use side block has additional ports built in to provide controlled air flow, if needed. The stainless steel sideblock has a built in EGS.
  • Whisker Wings - Bubble deflecting Whisker wings keep bubbles further from face port and ears, improving visibility and decreasing internal noise.
  • Pull Strap - Has been improved with the addition of a stainless steel “D” ring. This makes for easier removal. Pull Strap also allows the assembly to easily be hung for drying.
  • Positive-Lock™ Latch System - Developed by Kirby Morgan in 1992, consists of two sealed Positive-Lock™ pull pins which are pulled forward to release the neck collar and neck dam locking system. Even when the latches are released, the O-ring sealed neck dam maintains a positive seal and will not allow the seal to be broken until the collar actually clears the commercial diver’s shoulders, thus helping to prevent any flooding of the commercial diving helmet.
  • Head Cushion - Gives the commercial diving helmet a secure, well balanced feel as well as excellent thermal protection during long work periods.
  • Adjustable Neck Pad - Commercial Diving Helmet attached yoke system has an adjustable neck pad which is made from a scuff resistant elastomer. In conjunction with the spring activated front neck dam ring lock. Adjustable Neck Pad provides protection for the bottom of the commercial diving helmet
  • Kirby Morgan Rex® Demand Valve (patents pending), with it's full adjustment balanced piston is a breakthrough design that exceeds all requirements of all government or other testing agencies. It has the best work-of-breathing performance when compared to ANY other commercial diving helmet. This is our highest performing regulator, with the lowest breathing resistance and best work of breathing.


The Kirby Morgan Commercial Diving Helmet 77 has been tested and conforms to the performance requirements as set forth in Annex II of Directive 89/686/EEC and, as far as applicable, the EN 250:2000, EN 250/A1:2006 and EN 15333-1:2008 (class B). The Kirby Morgan Commercial Diving Helmet 77 is fully CE marked with demand valve REX.

  • Weight: 32.43 lbs.
  • Helmet Shell: Stainless Steel
  • Control Knobs: Polyurethane
  • Lens: Clear polycarbonate
  • Neck Dam: Neoprene. Optional latex neck dam available.
  • O-Rings: Buna-N
  • Head Cushion: Nylon bag filled with #4 Polyester foam
  • Recommended Lubricants: All commercial diving helmets and band masks are lubricated at the factory with Christo-Lube®. Kirby Morgan recommends Christo-Lube® or Tribolube® for all gas train components. Dow Corning® 111 Silicone or equivalent may be used for commercial diving helmet and band mask components that are used with gas mixtures containing less than 50% oxygen.
  • Kirby Morgan Rex® Performance: The Rex regulator on the Kirby Morgan Commercial Diving Helmet 77 offers high performance. The commercial diving regulator has been tested at Dive Lab at Panama City, Florida. The Kirby Morgan Rex® Commercial Diving Regulator meets or exceeds all current U.S. Navy and European commercial diving standards.
  • Cage Code: The cage code for identifying Kirby Morgan DSI products for U.S. government purposes is 58366.
  • CR Standards: Kirby Morgan Commercial Diving Helmets meet or exceeds all standards established by Dive Lab of Panama City, Florida, and are CR (Commercially Rated) marked.
  • CE Approved: The Kirby Morgan Commercial Diving Helmet 77 is CE Approved.

Kirby Morgan 77 Commercial Diving Helmet with Male Waterproof Connector - P/N: 500-091 Includes:

  • (1) Regulator Tool Kit with Pouch - P/N: 525-768
  • (1) Anode Kit - P/N: 525-375
  • (1) Manual KM 77 - P/N: 100-085
  • (1) Logbook with Pen - P/N: 120-001
  • (1) Helmet/Mask Bag - P/N: 500-901


The minimum operating temperature recommended for the Kirby Morgan 77 Commercial Diving Helmet is 37 degrees F, only in regards to regulator performance. At the time of this writing, no hot water shroud is available for the Kirby Morgan 77 Commercial Diving Helmet for heating the commercial diver’s breathing gas.

Without a Kirby Morgan Hot Water Shroud, the commercial diver may be subject to hypothermia due to cold gas inspiration temperatures. Kirby Morgan makes no physiological recommendations regarding minimum safe operating temperatures for commercial divers using the Kirby Morgan 77 Commercial Diving Helmet.

Usually the greatest danger of demand regulator icing will be encountered on deck when the surrounding air temperature is less than 32°F (0°C). This effect is primarily due to the refrigeration effect of breathing air pressure reduction, and the addition of moisture from the divers exhalation coming in contact with the topside air temperature.

Recommended overbottom (OB) gas supply pressure for best performance at depths are calculated by the formula (fsw x 0.445+14.7) + recommended p.s.i.g.


The Kirby Morgan 77 Commercial Diver's Helmet is a stainless steel commercial diving helmet with a rugged outer shell. The KM 77 features an all stainless version of the Kirby Morgan REX® Regulator, as well as a stainless steel sideblock, helmet ring, bent tube, handle, and other key components. The Kirby Morgan Rex Quad Valve® Exhaust System is standard on this commercial diving helmet.

The advanced regulator pod on the Kirby Morgan 77 will allow future versions of the Kirby Morgan 77 to be outfitted with other Kirby Morgan regulators, including the Kirby Morgan SuperFlow 350 Regulator or the all stainless steel Kirby Morgan SuperFlow 450 Regulator. The pod makes it possible to customize the Kirby Morgan 77 Commercial Diving Helmet with the diving regulator you want as job requirements change. The KM 77 does not require any refinishing if the surface is scratched or gouged, only comes in one color, and it eliminates threaded inserts for securing port retainer to helmet shell.

Warning: Before attempting any diving in any type of contaminated water, a complete commercial diving and topside course in hazardous materials emergencies should be completed. The commercial divers and the topside team must be properly trained and have the proper safety equipment. All commercial diving helmets and suits can leak water under certain conditions. Commercial divers should use extreme caution when diving in contaminated waters.

* Please reference the Accessories and Parts categories in the left hand column for all accessories and parts associated with the Kirby Morgan 77 Commercial Diving Helmet with Male Waterproof Connectors. Click on the KM77 and then the KM77 with Male Waterproof Connectors category and the Accessories and Parts categories will appear beneath it.

*For Questions on Kirby Morgan Helmet Retaining Systems, please refer to the bulletin in Documents tab which contains more detailed information.

Video Dive Helmet Maintenance (Spanish Subtitles)

Product FAQ's

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  • Why is my Stainless Steel Helmet Rusting?

    Kirby Morgan would like to assure all stainless steel helmet owners, that the helmet shells are not actually rusting. All of these helmet shells and other main components, are cast and machined from a highly corrosion resistant grade of 316L stainless steel. The investment casting process can produce a very good finish, but this still requires more processing to be acceptable. Each helmet shell is initially hand finished, then, it is processed to a very smooth surface using specialized friction finishing equipment. Even after all this processing, these smooth surfaces will still have small surface porosity that can trap foreign matter, some of which can “rust”. This is what will make the surfaces appear to be rusting. This foreign matter that may be trapped, needs to be cleaned away, and the surfaces need to be protected. Basic cleaning and protection should be performed on a regular basis and may need to be performed more often depending on what type of environment the helmets are used in. 

     NOTE, This “Rusting” issue can also be seen on Fiberglass helmet shells and chrome plated brass parts. It is what is stuck to those surfaces that is “rusting”. Not the fiberglass or chrome.

     Cleaning Procedures for the stainless steel helmet

    Thoroughly clean the components with a cleaning soap such as Simple Green. A soft scrubbing tool can help to remove excess materials. Dry the components and wipe completely with Isopropyl alcohol and allow to evaporate. Using a kitchen sponge with an abrasive side. Wet and apply hand soap that contains a slight abrasive (LAVA hand soap works very well, or Go-Jo Pumice, citric hand soap), and simply rub onto the affected area of the helmet shell. The unwanted stains will easily be removed.

     NEVER USE STEEL WOOL TO PERFORM THIS TASK. It will deeply imbed iron particles into the stainless and may cause severe rusting to the component.

    Citric acid or diluted vinegar can be used to passivate stainless steel and remove any light rust. A lemon half works well as a scrubbing tool, and at the same time provides the citric acid to help eliminate small surface particles of rust. Allow enough liquid to deposit on all affected surfaces and allow it to settle for at least 30 minutes. Rinse and re-apply as needed. Rinse again and finish wipe with the Isopropyl alcohol allow to dry completely.

    Apply at least 2 coats of a good quality paste wax. This will help seal surface porosity to prevent foreign matter from being trapped, which may then rust.

    It is best to clean as much of the helmet surfaces as possible, rather than cleaning only affected areas, as this will help prevent any future issues. A basic cleaning and waxing procedure should be performed as part of a routine cleaning regiment.

    Kirby Morgan suggests the use of lemon juice/lemons, or vinegar for the source of acid. These types of acid will help dissolve certain stains, rust and certain residue buildup such as hard water and mineral deposits. Because they are natural and non-toxic, Kirby Morgan highly recommends them for this procedure.

     NOTE: All new stainless helmet shells are electro chemical cleaned (electropolished) and friction polished to a very smooth exterior surface finish. If so desired, the surface can be brought to a higher luster using basic polishing techniques, (i.e. polishing compounds and light buffing techniques).

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  • What is the fitting type on the emergency valve?

    The threads at the end of the emergency valve are 9/16-18. A standard scuba hose, female (9/16"-18) will attach to them.

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  • What’s included with the Kirby Morgan 77 Commercial Diving Helmet?
    • User Manual – Part number 100-085
    • Logbook with Pen – Part number 125-001
    • Tool Kit with Pouch – Part number 525-768 
    • Helmet / Mask Bag – Part number 500-901
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  • Does Kirby Morgan sell a Hot Water Shroud Kit for any of the stainless steel helmets?
    Unfortunately, Kirby Morgan does not have a Hot Water Shroud Kit available for any of the stainless steel helmets at this time.
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