The Mastercool 90410 Flex Adapter is a must-have for any Aussie HVAC technician working with mini-splits and commercial refrigeration systems. Designed to convert a 1/4″ SAE hose to 5/16″ SAE (1/2″-20 UNF female flare), it offers a swivel connection for easier access in tight spaces—without twisting your hoses. Plus, it comes ready with a replacement gasket (82010) for a leak-free seal every time.

Key Features & Benefits

• Converts 1/4″ SAE hose to 5/16″ SAE (1/2″-20 UNF female flare)
• Swivel connection allows movement without stressing hoses
• Includes replacement gasket 82010 for reliable sealing
• Access valve core (90–110 PSI opening) included for service applications
• Durable brass construction built for trade use

How to Use

Simply screw the 90410 adapter onto your 1/4″ SAE hose, attach to your 5/16″ SAE fitting, and take advantage of the swivel action for faster, cleaner connections—especially handy in vertical or cramped installations.

Recommended Pairings

• Mastercool Digital Manifold Gauge – pair with the flex adapter for accurate pressure readings on mini-splits.
• Refrigerant manifold gauges and digital HVAC diagnostic tools – ideal upgrade if you're building or replacing your manifold setup.
• HVAC refrigerant hoses for manifold and service connections – find compatible 1/4″ SAE hoses for your setup.
• Using a flex adapter in HVAC setups – pro tips for maximising efficiency and avoiding leaks.

Watch It in Action

Built for the Field

With its swivel design and solid brass build, the Mastercool 90410 Flex Adapter is a small but mighty upgrade to your HVAC toolkit. Add it today and make your connections quicker, cleaner, and longer-lasting.