Circular connectors

Low/high voltage, coax/triax, hybrid, fiber optic, push-pull, circular, and even fluid/gas: 30,000 references support your power, signal and data requirements

Versatile solutions to meet your requirements

More than 70 years of world-renowned expertise, know-how and pioneering innovation in harsh-environment connectivity technologies such as ruggedness and endurance, sealing and hermeticity, miniaturization and high density, and faultless data transmission.


Wide range of shell sizes, keying options and pin configurations.

Circular connectors by application

All our series feature rugged connectors

Heavy-use or safety-critical applications must be designed to withstand specific levels of mechanical stress and environmental conditions without degrading power, signal, or data transmission.


To endure the toughest conditions, our circular connectors, cables and electronic solutions are built and assembled with robust materials and a rugged design:

  • Mechanical endurance to resist abrasion, wear, and intensive use – up to 10,000 mating cycles without any loss of signal or power
  • Design and assembly robustness – resistance to vibration and shock, safe and extremely robust locking (push-pull, breakaway, screw) and keying (with easy error-proof blind mating as well as color-coding identification), mating-rotation resistance, ultra-resistant resin sealing (body and contact block), cable tensile strength up to 400 N (central strength member)
  • Material mix (housing, plating, insulating, sealing, overmolding, jacketing) for increased hardness, flex endurance and resistance to environmental conditions such as high temperatures, radiation, corrosion and salt fog, chemicals (sterilization, disinfection and decontamination proof)
  • 360° shielding ensuring EMI/RFI protection for faultless data transmission (data integrity and security).



‘Ruggedization’ methods and processes pertain to the entire designing, engineering and manufacturing chain of our circular connectors, cable assembly and electronic solutions – from choosing high-quality materials for housing, coating, plating, insulating and sealing, to overmolding or jacketing cables to protect the insulation and conductor core against environmental aggression and chemical deterioration, etc.

Resistance of our materials

Check out which material is most suitable for your application.

Discover more about our rugged circular connectors

Our original push-pull locking system


The plug’s outer sleeve, with flexible fingers, slides forwards and backwards along the body.

When connected

The beveled edges are firmly captured by a locking groove located inside the receptacle.

Pulling the cable

The beveled edges of the fingers are forced into the groove, securing the connection.


Pulling on the outer sleeve of the plug unlocks the latching mechanism.

Other locking systems

Resistance to extreme conditions

Extreme temperature resistance

Our most rugged series offers standardized products that operate within the temperature range of -55 °C to +135 °C, tested in compliance with the Military Standard 810 Methods 501.6 and 502.6.


With the right insulator and cable clam set, Fischer Core connectors can even withstand temperature ranges from -70 °C to +250 °C (and -100 °C upon request).


Cabled circular connectors overmolded with TPU material withstand temperatures ranging from -40 °C to +125 °C. As for soft caps, they resist a maximum temperature of +85 °C.

Corrosion resistance

Protection against corrosion mechanisms – pitting, intergranular or crevice – is achieved by choosing the right materials and type of coating. The most common materials and coatings used are:


  • Brass with nickel or chromium coating
  • Stainless steel, which is one of the best materials for corrosion resistance, since corrosion protection is embedded within the material itself.


Tested in compliance with standards IEC 60068-2-11 Test Ka, MIL-STD-202 Method 101, and EIA-364-26, our products go through long-standing exposure (1,000 hours) to a 5% salt solution (salt fog) at a temperature of 35 °C without any impact on their mechanical or electrical functionalities.

Sterilization proof

If you’re in need of high-performance connectors that withstand most sterilization methods, consider the Fischer Core Series. These circular connectors are made with premium materials making them capable of withstanding temperatures ranging from -70 °C to +250 °C.


Available in IP68/IP69-sealed and hermetic versions, the circular connectors are designed to resist even the harshest conditions like the highly pressurized steam of autoclaves, delivering the heat able to kill microorganisms in 30 minutes.

Vibration and shock resistance

Tested in compliance with MIL standard 202 Method 214 and Condition I, our connectivity solutions resist random vibration of up to 37.80 Grms for our most rugged series. Mounted onto vibration equipment, the locking and contact specifications of a circular connector pair are thoroughly verified.


Electrical signals are monitored to ensure that no micro-cuts smaller than one micro-second occur. Examining electrical signals is also performed to ensure that our connectivity solutions can withstand shocks of up to 300 g amplitude (half-sine pulse of 3 ms, no discontinuity > 1 μs) and withstand drop-resistance tests, by measuring the mechanical deformation that could impact the connection’s functioning.

Chemical resistance

In hospital sterile environments, dentistry and laboratory settings, as well as in food and pharmaceutical processing, devices and equipment must be cleaned, disinfected and sterilized on a regular basis.


Our products’ components – shells, contact blocks, O-rings and seals, cable jackets, etc. – are made of ultra-resistant materials to withstand the conditions incurred by sterilization methods with chemicals such as Steris LCS, Sterrad and EtO.


They also endure exposure to chemicals in oil, gas and petrochemical environments such as aliphatic hydrocarbons, oils or fuels, greases, detergents, dilute acids and bases, and most aqueous salt solutions.

Radiation resistance

Radiation resistance is required for long-lasting tasks in nuclear or contaminated environments such as handling heavy radioactive loads, performing inspections, and repairing equipment – sometimes performed remotely by robot workers due to inaccessibility or the danger of radiation exposure.


Our radiation-resistant connectivity solutions made of stainless steel are easy to handle with gloves and remotely, and are compatible with nuclear-decontamination fluids, offering a premium material mix and sealing performance.


Radiation-resistant circular connectors are also required to sterilize by gamma irradiation (typically Cobalt 60) medical devices and equipment whose materials cannot withstand the high temperature of steam autoclaving.

Proven and tested

Off-the-shelf, customized or tailored to your needs, our high-performance solutions are designed to last.


In order to reach the highest reliability and quality standards, our circular connectors go through a battery of mechanical and environmental tests, in compliance with industry and military standards such as IEC, EIA, MIL-STD-202 and MIL-STD-810.


Watch here some of the tests and proofs we conducted in our laboratory and in the field on the Fischer LP360™ 7-contact connector.

Search our most popular products to find your solution.