Our Solutions
Conductive Elastomer Flange Gaskets
EMI Flange Gaskets are used between the connector flange and mounting bulkhead to provide an environmental seal and an EMI shield. These gaskets are designed for use with MIL-C-28840, MIL-C-38999, MIL-C-81511, MIL-C-5015, MIL-C-83723, MIL-NAS-1599, MIL-C-26482 and MIL-M-83528 connectors. They are typically manufactured from CHO-SEAL-1212™, CHO-SEAL-1285™ and CHO-SEAL- 12249™.
Proficiencies
Proven Knowledge
Deep engineering capabilities with expert knowledge of EMI RFI specifications
Field Proven
1,000’s of designs integrated into battle-harsh and commercially challenging environments
Proven Track Record
Orders delivered on time and to specification
Performance
From initial production design to full scale production
Continuous Improvement
Driven to maintain a zero-return rate
Collaborating
From project concept until completion
One gasket that seals
the connector, shields the joint.
EMI flange gaskets sit between the connector flange and the mounting bulkhead — providing a full environmental seal and a continuous EMI shield across the interface. Converted from conductive elastomer to the mounting pattern of your connector series, prototype through production.
ISO 9001:2015 · ITAR Registered · MIL-DTL-83528 · Made in USA
MIL connector families
fitted to pattern
Shielding effectiveness
on silver grades
Driven to hold a
zero-return rate
Quote turnaround
no minimum order
Flange
interface
Connector flange ↔ bulkhead
Environmental seal + EMI shield
CHO-SEAL conductive elastomer
Up to 120 dB · silver fills
24-hour quote · no minimum
Sealing the connector,
grounding the shell.
Every panel-mounted connector is a hole in an otherwise shielded enclosure. The flange gasket closes that hole electrically and environmentally at the same time — a single conductive elastomer part captured under the connector flange.
Interference and moisture both find the gap where a connector meets its bulkhead — a conductive flange gasket closes it.
Under the compression of the mounting hardware, the filled elastomer forms a continuous low-impedance path between the connector shell and the enclosure wall, equalizing potential and routing induced currents to ground.
The same part carries an environmental seal — blocking moisture, dust, salt fog, and pressure differentials — so the interface stays sealed and shielded through vibration, thermal cycling, and field service.
01
Between flange and bulkhead
The gasket is captured at the connector mounting interface, compressed as the connector is torqued to the bulkhead — closing the joint the moment the hardware is installed.
02
Seal and shield in one part
A conductive elastomer body blocks moisture, dust, and pressure while establishing a low-impedance ground path around the connector shell — no separate shield or O-ring stack.
03
Cut to the mounting pattern
Bolt-hole circle, shell cutout, and profile are converted to match your connector series exactly — round, D-shape, or fully custom outline per drawing.
04
Field-proven durability
Grounded across thousands of designs in battle-harsh and rugged commercial environments, converted to hold up over the full service life of the interface.
Fitted to your
connector series.
Flange gaskets are converted to the mounting pattern of the connector they seal. We routinely cut to the standard MIL and NAS series below — send the connector part number and we’ll match the pattern.
Series I–IV · circularSeries I–IV · circularBayonet / threadedPrimary aerospace & defense circular connector — the most widely fitted flange gasket.
Circular · powerCircular · powerThreadedRugged industrial and power connectors for ground support and heavy equipment.
Series 1 & 2Series 1 & 2Bayonet / threadedCompact environment-resisting connector for avionics and instrumentation.
High-density · shipboardHigh-density · shipboardThreadedHigh-shock, high-density shipboard and naval electronics interfaces.
Rack & panelRack & panelBayonetMiniature rack-and-panel connectors for dense enclosure back-planes.
Series I–III · firewallSeries I–III · firewallThreadedEnvironment-resistant, firewall-rated connectors for engine and airframe.
Rear-release crimpRear-release crimpThreadedHigh-reliability rear-mounted crimp-contact connector standard.
Gasket material specGasket material specConductive elastomerThe controlling material specification our conductive elastomer grades meet.
Compatible with MIL-C-28840, MIL-C-38999, MIL-C-81511, MIL-C-5015, MIL-C-83723, MIL-NAS-1599, MIL-C-26482, and MIL-M-83528 connectors, among others. Gaskets are converted to the specific shell size and mounting pattern — send the connector part number or drawing for an exact match.
Proven conductive
elastomer grades.
Flange gaskets are typically manufactured from CHO-SEAL™ conductive elastomers. We convert the grade your specification calls for — matched to enclosure metal, frequency band, and environment.
Silver-plated aluminum in silicone
The workhorse conductive elastomer for flange gaskets — a strong balance of shielding, corrosion resistance, and cost across aluminum enclosures.
Silver-plated copper in silicone
Highest volume conductivity of the group — the choice where shielding effectiveness and low-impedance grounding are the priority.
Silver fill in fluorosilicone
Silver-based fill in a fluorosilicone binder for improved fuel, oil, and solvent resistance while retaining strong shielding performance.
CHO-SEAL™ is a trademark of its manufacturer. Shielding effectiveness values are representative of conductive elastomer systems per modified MIL-DTL-83528 test method and vary with frequency, flange design, and compression. Send your specification — we’ll confirm the grade and performance against your interface.
Flange gaskets
built to spec.
Published capability across conductive elastomer flange gaskets. Shielding, durometer, and mounting pattern are verified against your connector series and enclosure.
Non-standard flange?
We regularly deliver
custom flange gaskets
beyond catalog patterns.
Send your print and connector part number. If we can convert it, we’ll quote it.
Where our flange
gaskets ground.
From avionics LRUs to shipboard connector banks, PNA flange gaskets seal and shield the connector interface across programs where reliability is not optional.
01 / 06
Aerospace & Defense
- Avionics connector sealing
- Radar & sensor enclosures
- Firewall-rated interfaces
- Battle-harsh environments
02 / 06
Uncrewed Systems
- UAV / UGV connector joints
- Payload bulkhead sealing
- Lightweight silver-Al grades
- Vibration-resistant install
03 / 06
Space & Satellite
- LRU enclosure interfaces
- Low-outgassing compounds
- Ground-path continuity
- Mass-optimized fills
04 / 06
Ground Vehicles
- Rugged mil connector seals
- Shock & dust protection
- MIL-DTL-5015 power joints
- Field-serviceable parts
05 / 06
Naval & Shipboard
- MIL-DTL-28840 high-density
- Salt-fog & moisture sealing
- High-shock survivability
- Corrosion-resistant fills
06 / 06
Rugged Commercial
- Industrial connector sealing
- Telecom enclosure joints
- Test & instrumentation
- EMI compliance builds
Proficiencies
& performance.
Deep engineering capability, materials in stock, and a quality system built around defense and aerospace compliance from day one.
Field proven
Thousands of designs integrated into battle-harsh and commercially challenging environments — interfaces that hold up where it counts.
Proven track record
Orders delivered on time and to specification, from initial production design through full-scale production.
Continuous improvement
Driven to maintain a zero-return rate — quality and performance improvement built into every program.
Deep engineering
Expert knowledge of EMI/RFI specifications and connector interfaces, collaborating from project concept until completion.
More from the
PNA capability set.
Conductive flange gaskets are one family on a single CAD-driven production floor. Explore the rest of what we convert.
01 / 06
Conductive elastomer shielding gaskets converted to print — silver, copper, and nickel-graphite fills per MIL-DTL-83528.
02 / 06
EMI O-rings that shield and seal in one part across silicone and fluorosilicone binders, plus the full elastomer range.
03 / 06
Gap pads, phase-change, and adhesive TIMs that dissipate heat and conform to uneven surfaces.
04 / 06
High-performance environmental gaskets converted from silicone, EPDM, Viton, and neoprene grades.
05 / 06
Dielectric components cut from Nomex, Mylar, and Kapton for battery packs and HV enclosures.
06 / 06
Tier-one stocking relationships across the leading EMI, thermal, and sealing material manufacturers.
Need custom flange
gaskets? Quotes in 24 hours.
Include the connector series or part number, material grade, shielding requirement, and quantity. We’ll respond within 24 business hours with feasibility, lead time, and price.
Connector-matched patterns · custom flanges · small-batch · measurement reports