These large winged radiator pressure caps are designed for classic, commercial, agricultural, and industrial cooling systems requiring a 68 mm filler neck. Manufactured with a zinc-coated steel case and brass valve components, they provide reliable pressure regulation and long service life.
The wide winged design (90 mm overall) allows easy fitting and removal, even in tight or heavy-duty engine bays. Each cap is correctly sprung and pressure-rated to maintain optimal coolant system performance while protecting hoses, radiators, and seals.
Available in multiple pressure ratings to suit a wide range of applications.
Key Features
Large winged radiator pressure cap
Zinc-coated metal case for corrosion resistance
Brass valve assembly with rubber sealing washer
Easy-grip winged design
Suitable for classic, commercial, plant, and agricultural vehicles
Multiple pressure ratings available
Technical Specifications
Specification
Details
Cap Outside Diameter
70 mm
Overall Width (inc. wings)
90 mm
Filler Neck Fitment
68 mm diameter
Required Filler Neck Depth
19 mm
Spring Length
21 mm (brass washer to spring end)
Rubber Seal Diameter
51 mm
Case Finish
Zinc coated
Valve Material
Brass
Pressure Ratings Available
4lb, 7lb, 10lb, 15lb
Available Variants
4lb – Low-pressure systems
7lb – Light commercial and classic vehicles
10lb – Standard cooling systems
15lb – Higher-pressure applications
(Select required pressure rating from the dropdown menu.)
Compatibility Notes
Fits radiator filler necks with 68 mm internal diameter
Requires 19 mm inner neck depth
Always match pressure rating to manufacturer specifications
Not suitable for non-pressurised systems
What’s Included
1 × Large Winged Radiator Pressure Cap (selected pressure rating)