LockNLube Giant Button Head Grease Coupler 7/8" – 1/8" FNPT, 3,000 PSI Working Pressure

The LockNLube Giant Button Head Coupler 7/8" is a heavy‑duty grease coupler engineered to fit 7/8" button‑head grease fittings for high‑volume lubrication work.

Designed for mechanics, fleets, and industrial maintenance teams, this coupler provides a secure, high‑flow connection to oversized button head fittings. It combines a robust pressure rating with a 1/8" FNPT connection, making it simple to integrate with standard grease guns and hoses for fast, reliable lubrication of bearings, pivots, and large fittings.

How does the 7/8" Giant Button Head Coupler handle high‑volume grease jobs?

The oversized 7/8" opening and internal geometry let grease pass quickly without bogging down the gun. That makes it well suited for large bearings and heavy equipment that require generous amounts of grease per cycle.

• 7/8" (22 mm) button‑head compatibility for large fittings
• Rated to 4,000 PSI for peak pressure tolerance
• Working pressure of 3,000 PSI for regular operation
• 1/8" FNPT thread for easy attachment to common grease hoses

Will this coupler stay attached to button‑head fittings during use?

Yes — the coupler’s design provides a secure engagement around button‑head fittings to minimize slippage while pumping grease. Its geometry and material choice reduce the likelihood of blow‑offs under normal working pressures.

• Snap‑on/press fit profile for firm seating on 7/8" heads
• Durable construction resists deformation under load
• Compatible with typical grease gun coupling techniques

How do I connect the LockNLube coupler to my existing equipment?

Connecting is straightforward: thread the coupler onto a matching 1/8" FNPT hose or adapter, then press the coupler onto the 7/8" button head and operate the grease gun as usual. No special tools are required for standard installations.

• Thread: 1/8" FNPT fits standard grease hoses and adapters
• Installation: hand‑tighten or use common plumbing tools as needed
• Works with high‑capacity grease guns and pneumatic systems

What pressures and conditions is this coupler rated for?

The Giant Button Head Coupler is built for demanding environments and is rated for both working and peak pressures encountered in heavy lubrication tasks. It’s intended for grease, not for pneumatic fluids or hazardous media.

• Working pressure: 3,000 PSI for routine use
• Maximum rating: 4,000 PSI for intermittent peaks
• Ideal for high‑volume, heavy‑equipment lubrication cycles

Who this is for: The LockNLube Giant Button Head Coupler 7/8" is aimed at professional mechanics, agricultural and construction maintenance crews, fleet service shops, and anyone who services large bearings or heavy machinery that uses 7/8" button‑head grease fittings. If you need fast grease delivery, a dependable hookup, and compatibility with standard 1/8" FNPT hoses, this coupler is built to meet those needs.