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Molex KK Connectors

KK Connectors

The KK Connector System includes wire-to-board and board-to-board solutions that deliver design flexibility and reliable electrical connectivity. KK connectors are engineered for low-to-mid-power applications, while KK Plus connectors provide quality solutions for high-power needs. Manufacturers can save time and money with KK products, as they offer diverse configurations for streamlined designs and efficient assembly.

PCB Headers

Molex KK 254 PCB header.

PCB Receptacles

Molex KK 396 PC board connector.

Connector Housings

Molex KK crimp housing

Crimp Terminals

Molex KK crimp terminals

Connector Accessories

Molex KK TPA retainer

Cable Assemblies

Molex KK cable assembly

Features and Benefits


The KK Connector System is a trusted choice in the industry due to their durable and reliable wire-to-board and board-to-board solutions. These connectors are suitable for a wide range of low-to-mid-power applications and provide ease of use through their friction lock and polarization features that help prevent mis-mating.

Environments that demand repetitive mating when assembling connectors can also lead to problems such as terminal back-outs, ultimately resulting in end-product failures. With locking mechanisms designed to secure mating, KK connectors help prevent terminal back-outs during connector assembly. These connectors also feature a variety of pitch sizes and circuit sizes to accommodate different design requirements, ensuring a versatile fit for various electronic assemblies. The KK Plus series expands on these capabilities by offering solutions specifically tailored for high-power applications, maintaining the design flexibility and efficiency that are characteristic of the KK series.

These robust connectors are engineered to handle higher currents and are equipped with additional safety and retention features, making them ideal for more demanding environments where power integrity is crucial. The KK and KK Plus systems are both designed with the end user in mind, ensuring secure connections and simplified assembly processes across a multitude of industries.

  Style Pitch Current Circuits Wire Gauge Operating Temperatures
KK 254 Wire-to-board, Board-to-board 2.54mm Up to 7.0A 1 to 40 30 to 18 AWG -40° to +105°C
KK 396 Wire-to-board, Board-to-board 3.96mm Up to 7.0A 1 to 40 30 to 18 AWG -40° to +105°C
KK 508 Wire-to-board, Board-to-board 5.08mm Up to 7.0A 1 to 40 30 to 18 AWG -40° to +105°C
KK Plus Wire-to-board 2.50, 3.00, 3.96mm Up to 11.0A 2 to 8 28 to 18AWG -40° to +105°C

KK 254, KK 396, KK 508 Connector Systems

Enhances electrical reliability
Dual cantilever terminals​ provide dependable electrical connectivity.

Prevents accidental disengagement and provides secure mating​
Polarizing options and friction locks​ help to avoid mis-mating.

Meets European standard for electrical requirements​
KK 396 and KK 508 connectors are Glow Wire capable.

KK Plus Connectors

Provides connection assurance
The positive-locking latch has a clear, audible click.​

Helps prevent mis-mating​​
These connectors offer a unique keying design.​

Meets European standard for electrical requirements​
KK Plus connectors are V-0/Glow Wire capable.

Documents and Resources


Applications by Industry


Countertop appliances
Dishwashers
Dryers
Fire alarms/smoke detectors
Freezers
Gaming machines
Home security systems
HVAC equipment
Microwaves
Ovens
Refrigerators
Scanners
Security systems
Washing machines

Charging stations
Control modules
Harness manufacturers
Interior lighting equipment
Internal devices
Non-sealed applications
Stereos
Window defrosters

Assembly line equipment
Automation equipment
Food and beverage equipment
Industrial networks
Robotics

Blood warming bags
Dental equipment
Diagnostic devices
Heart monitors
Patient monitors
Portable diagnostic equipment
Respirators

Copiers
Multi-function scanners
Office equipment
Printers
Scanners/multi-function machines

Mainframes
Routers and switches
Servers
Storage systems
Workstations

This is not a definitive list of applications for this product. It represents some of the more common uses.

Frequently Asked Questions


What are KK Connectors?

KK Connectors are modular wire-to-board and board-to-board interconnect solutions designed to deliver reliable power and signal connections in a wide range of electronic applications. The family includes KK 254, KK 396 and KK 508 systems with 2.54, 3.96 and 5.08mm pitch options, as well as KK Plus Connectors with enhanced locking and retention features. Depending on the series, configurations support up to 40 circuits, currents up to 11.0A and wire sizes from 30 to 18 AWG.

Which pitch size should I choose: 2.54, 3.96 or 5.08mm?

Pitch selection depends on current requirements, available board space, wire size and connector density. Smaller pitches help reduce PCB footprint, while larger pitches support higher current-carrying capability and reduce arcing risks.

How much current can KK Connectors support?

Current ratings vary by series and specific part numbers. The KK family supports up to 7.0A, while KK Plus Connectors support up to 11.0A. Engineers should always verify electrical performance using the product-specific datasheet and application requirements.

What wire sizes are supported by KK Connectors?

Standard KK systems support 30 to 18 AWG wire, while KK Plus Connectors support 28 to 18 AWG.

Are KK Connectors suitable for applications exposed to vibration?

Many KK Connector options include friction locks, polarization features and retention mechanisms to help prevent accidental disengagement. For applications requiring additional mating security, engineers may consider KK Plus solutions with positive-locking latch and terminal position assurance (TPA) options.

What options are available to help prevent connector mis-mating?

KK Connectors offer polarization features and friction locks to help ensure proper mating. KK Plus Connectors add unique keying designs and positive-lock retention that further reduce the risk of assembly errors.

Can KK Connectors support automated PCB assembly processes?

Certain KK product options include reflow-capable headers and other assembly-friendly features that support modern manufacturing processes. Engineers should review the selected series of documentation to confirm compatibility with their assembly requirements.

Are KK Connectors available in both wire-to-board and board-to-board configurations?

Yes, the KK connector family offers both wire-to-board and board-to-board products, providing design flexibility for a wide range of electronic interconnect architectures.

In what industries are KK Connectors commonly used?

KK Connectors are commonly used in appliance, industrial, consumer, medical and general electronics applications that require dependable power or signal connections and flexible design options.

How can I reduce assembly errors and terminal back-out during production?

KK products provide connector retention features such as friction locks and polarization. KK Plus products additionally offer positive locking and optional TPA features that help secure terminals and improve assembly quality.

How do I know if a KK Connector is the right choice for my application?

KK Connectors are designed for low-to-mid-power, wire-to-board and board-to-board applications requiring reliable electrical connectivity, multiple pitch options and a wide range of circuit counts. Engineers should evaluate current requirements, available PCB space, wire gauge, mating frequency and environmental conditions when selecting the right KK Connector.