• Compact & miniature
• Lightweight & low-profile
• High vibration resistance
• IP68 & MIL-STD tested
Your optimised solution

Designed for use in severe environmental conditions replete with electrical, mechanical and environmental stressors, LEMO’s series meets a wide range of complex requirements. Extensive testing ensures its compliance in terms of chemical, thermal and mechanical properties, to suit the most varied and critical applications.  Excellent shielding, vibration and shock resistance, in addition to excellent sealing specifications, are all part of LEMO’s high quality and durability strategy, which translates into increased connection safety and reliability. Investing in the built-in reliability and longevity of LEMO’s interconnect solutions helps to guarantee cost-effectiveness.

From ergonomics to signal integrity through dedicated layout 

Always one step ahead, and able to meet modern technology’s ever-increasing demands for smaller weights and sizes, LEMO’s   Demanding Environment connector series features an innovative ultra-compact and lightweight format that is both easy to use and ergonomic. Available in either Push-Pull, Break-Away or screwor the highly robust rachet 3/4 turn locking system, our connectors provide absolute signal integrity in a smaller footprint compared to the Mil-38999 series, enabling further customer device miniaturisation.

Setting new standards

LEMO’s field-proven, cutting-edge connection solutions are integral to the success of the challenging applications in which they are employed, including defence and security, motorsports and transportation. Some models have even been adopted as the ‘de facto’ standard, such as the F series in Formula 1, IndyCar and the Le Mans 24-hour endurance auto race. 



Use the table to compare the 2 main series within the OPTIMA connector family and to identify the connector(s) best adapted to your specific requirements.
M - Rugged Ratchet coupling

M - Rugged Ratchet coupling

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F - Rugged Push-Pull

F - Rugged Push-Pull

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Description Description LEMO lightweight, compact, high vibration resistant (Mil STD 202 & 810F), IP68 screw locking connector Description LEMO lightweight, compact, high vibration resistant (Mil STD 810F), IP67 Push-Pull connector
Locking Locking Triple start, 3/4 turn rachet coupling Locking Push-Pull
Size Size 9 sizes from ø 11.1 to ø 34.0 mm (plugs) Size 9 sizes from ø 8.5 to ø 36.1 mm (plugs)
Keying Keying 6 keyway options Keying 4 keyway options
Shell Types Shell Types Over 40 shell styles Shell Types Over 12 shell styles​
Shell Material Shell Material Aluminium or Brass Shell Material Aluminium or Brass
Plating Plating Antracite nickel or Chrome Plating Antracite nickel or Chrome
Cable Diameter Cable Diameter 2.2 to 34 mm • 4 backshell options available Cable Diameter 2.2 to 34 mm • 1 backshell option
NB of contact NB of contact 3 to 114 NB of contact 3 to 66
AWG AWG LV 16 to 32 mm • Hpower 1 to 8 mm AWG 18 to 32 mm
Contact types Contact types Multipole • Coax • Fibre Optic • Fluidic Mixed • High power Contact types Multipole • Fibre Optic
Contact Termination Contact Termination Crimp / Print (PCB) Contact Termination Crimp / Print (PCB)
Data Protocols Data Protocols USB 2.0 / Eth Cat6 Data Protocols -
Sealing level Sealing level IP68 / hermetic sockets Sealing level IP68 / hermetic sockets
Temperature range Temperature range -55°C to 200°C Temperature range -55°C to 200°C
Mating Cycles Mating Cycles > 3000 Mating Cycles 300 / 5000 acc. to sizes/material
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F series - Motorsport/Defense
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M series catalog
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Solutions Selection Guide
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Product brief - High-speed data transfer
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Product brief - M series High Power
Other documents
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No matter how harsh the environment may be, LEMO has a solution ready for you to implement today.

If not, we promise to relentlessly innovate and develop one for you. 
Please take a moment to reach out and describe your project, technical specifications and deadlines. We are standing by and looking forward to hearing from you - and adding your business to our thousands of longstanding satisfied customers, partners and employees - very soon.