HK Industries

A double handle grease coupler with lock is a specialized attachment used with grease guns to securely connect to a grease fitting (also called a nipple or Zerk fitting) during lubrication. It features two opposing handles that the user squeezes to open the coupler jaws, allowing it to easily snap onto the fitting; once released, the jaws clamp tightly in place. The built-in locking mechanism holds the coupler firmly attached without requiring continuous hand pressure, which helps prevent grease leakage and accidental disconnection during use. This design improves efficiency, reduces mess, and allows for hands-free operation in tight or high-pressure lubrication tasks, making it especially useful in automotive, industrial, and heavy machinery maintenance.

A grease nipple protective cap (also called a grease fitting cap or zerk cap) is a small cover that fits over grease nipples to keep them clean and functional.

• Prevents dust, dirt, and moisture from entering the grease fitting
• Stops contamination of lubrication points, which can damage bearings and joints
• Helps extend equipment life and reduce maintenance

They’re usually made of plastic (LDPE) or sometimes rubber and are designed to push-fit over standard grease nipples (commonly 6 mm / M6–M10 sizes)