Qualified Military and Commercial Hermetic Connectors for Harsh-Environment, Air-Tight-Seal Applications
Hermetic connectors are highly engineered Mil/Aero interconnect devices designed to maintain an air-tight seal in extreme environments. Using glass-to-metal sealing or advanced encapsulant technology, these hermetic seal connectors prevent moisture ingress, resist pressure differentials, and protect sensitive electronics in mission-critical systems. From submarines and oil-and-gas equipment to orbiting satellites, laboratory vacuum chambers and commercial or military aircraft, hermetic connectors ensure long-term reliability wherever environmental sealing is essential.
Glenair supplies a broad range of hermetic seal connectors — including MIL-DTL-38999 Series I, II, III, and IV — originally developed for military aerospace hermeticity requirements. Today, these ruggedized, air-tight connectors are also widely used in commercial sectors such as energy exploration, industrial instrumentation, and medical devices.
Engineered for extreme application conditions, Glenair hermetic connectors safeguard high-value payloads and electronics in environments characterized by severe weather, high altitude, rapid temperature changes, and vacuum exposure. Applications include sealed black-box enclosures, UAV payload systems, precision sensors, and other electronics that depend on consistent pressure-tight and moisture-barrier performance.
While glass-to-metal sealing remains the industry benchmark, Glenair’s next-generation CODE RED™ encapsulant hermetic technology offers mission-critical sealing with improved electrical performance and significant weight reduction — a major advantage in modern aerospace and unmanned systems.
Zero or Near-Zero Gas Leakage (Hermeticity)
Both Glenair CODE RED and glass-to-metal seal hermetic connectors deliver a qualified air-tight seal to prevent the passage of gases — not just liquids — through the connector interface. In Mil/Aero hermetic connectors, this is quantified using leak-rate limits such as:
- ≤ 1×10⁻⁷ atm-cc/sec helium
- Verified via helium fine-leak and gross-leak testing
- Rated operating temperatures -115°C to 200°C (-175°F to 392°F)
NASA Standards
Glenair supplies hermetic feed-thrus and hermetically-sealed receptacle connectors that meet the following NASA standards for interconnects used in manned spacecraft:
- NATC (NASA Threaded Coupling)
- SSQ21635 (NASA standard for circular, mostly hermetically sealed connectors used in manned spacecraft)
- NASA-STD-8739 (NASA assembly standard for cable systems on the ISS, ESCC manufacturing standards are compliant)
Military Standard Configurations Include:
- Hermetic power inserts based on MIL-DTL-5015 in shell sizes 25L to 37
- Signal hermetic designs IAW MIL-DTL-38999 Series I, II, III, and IV
- Rectangular MIL-DTL-24308 hermetic receptacles
- MIL-PRF-83513 type Micro-D hermetic connectors
- MIL-DTL-26482 Series I and II type power and signal hermetic designs
- MIL-DTL-83723 Series III threaded and bayonet hermetics
Glenair Signature "Better-than-QPL" Hermetic Connector Configurations Include:
- Series 80 Mighty Mouse Lightweight Circular Hermetics
- Series 806 Mil-Aero Micro Miniature Hermetic IAW MIL-DTL-38999 Series III
- HiPer-D MIL-DTL-24308 Intermateable Hermetic Connectors
- Series 79 High-Density Hermetic Rectangular Connectors
- PowerTrip High-Density Hermetic Circular with Power Inserts
- Geo-Marine Harsh-Environment Hermetic Connectors
CODE RED™ Lightweight Hermetic Sealing Connectors
Click to see our full line-up of CODE RED Lightweight Hermetic Sealing Connectors
Glenair Worldwide Hermetic Capabilities Video
Hermetic Leak Rate Testing Limits and Qualification for Connectors Used in Military and Aerospace Applications
Hermetic sealing is central to the long-term reliability of military and aerospace electronics. Hermeticity—defined simply as the condition of being airtight—prevents the ingress of moisture, outgassing products, and contaminants that can degrade electronics or lead to failure over the life of a mission.
Mil-Qualified and Glenair Signature Hermetic-Class Connector Datasheets
Introduction to Hermetic Seal Connectors
- Introduction to Glenair Hermetic Seal Connector Products
- Space-Grade Application Guidelines for Hermetic Connectors
- Hermetic Connector Helium Leak Rates and Testing
- Hermetic Connector Designer's Application Checklist
Hermetic Connector Modification Codes
PC Tail Termination Note
To prevent detrimental intrusion of cleaning solvents/water into the connector when terminating, the connector must be protected IAW IPC J-STD-001 and/or NASA STD-8739.3. For assistance and/or additional information, please contact factory.
Hermetic Connector Tech Tips: Application Notes on Mounting and Termination of Hermetic-Seal Connectors
- Sealing Square Flange Hermetic Connectors with Blind Mounting Holes
- O-Ring Mounting Square Flange Hermetic Connectors
- Crimp-contact termination of hermetic connectors with Glenair’s innovative "backpack" contact solution
Related Glenair Connectors
- CODE RED™ Lightweight Hermetic Sealing Connectors
- Miniaturized Circular Connectors (38999, 28840, 5015, and Other Cylindrical Designs)
- Rugged Connectors for Geophysical and Offshore Applications
Hermetic Seal Connectors
Military QPL and Commercial Connectors for Harsh Environment Air-Tight-Seal Applications
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MIL-DTL-38999 QPL and Glenair Signature SuperNine
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Series 80
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Series 806
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Geo-Marine® Series III Type
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QPL Hermetic MIL-DTL-24308
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MIL-DTL-83513 Type
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Series 790 High-Density and 791 Scoop-Proof
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Series 970 PowerTrip®
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High-Pressure, High-Temperature Hermetic Feed-ThrusFor Oil and Gas Industry Applications |
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Series GRF
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MIL-DTL-26482 Series I and II Type
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MIL-DTL-83723 Series III
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MIL-DTL-26500 Type
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MIL-DTL-5015 Type
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