What pressure ratings are available?

We stock radiator caps in multiple ratings, including 13psi (0.9 bar), 16psi (1.1 bar), and higher for performance applications.

Are these caps universal or vehicle-specific?

Most caps are designed to fit standard filler neck sizes, but we also offer specific fitments for certain radiators and header tanks

What materials are used in these radiator caps?

Our radiator caps are made from steel, brass, or plated zinc with rubber seals to ensure leak-free operation.

Radiator Caps | Pressure Relief Caps for Cooling Systems

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Protect Your Engine with the Right Radiator Cap

Radiator caps do more than just seal your cooling system — they regulate pressure, improve boiling point, and allow safe coolant overflow. Choosing the correct pressure cap helps prevent overheating and ensures optimal system performance.

Available Pressure Ratings and Fitments

Low, medium, and high-pressure caps from 0.9 bar to 1.5 bar
Standard neck and small cap styles
Plain and decorative polished finishes

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All radiator caps are in stock and ready for next day UK delivery. Keep your cooling system sealed, pressurised, and protected.

Car Builder Solutions

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3419 reviews

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Based on 3419 reviews

Wide selection of car parts available at good prices, perfect for building or repairing a car.
Fast and reliable delivery service, ensuring quick receipt of ordered items.
Helpful and knowledgeable staff in-store, providing excellent customer service and assistance.

Robert Williams

a week ago

Verified

Have used them online loads, but popped in for the first time for something quickly. Very helpful and had exactly the random part I needed. Perfect!!

allan gray

a month ago

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if you are building a car this is the place to go for your parts and at good prices , the delivery service is fast and very well packaged, highly recommended.

D S.

a month ago

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A great store for true car enthusiasts! I find things here that are impossible to find in the US!

Caitlin Curtis

4 months ago

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Amazing service! Placed an order at 4pm and received before 9am the next morning! As a Classic car restoration company, this is brilliant service for our tricky jobs!

Nick Payne

10 months ago

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fast service, prompt delivery, good choice of items on the website would just like to add the product has held up to 3 years of use now (far outlasting anything else that had been tried) kevlar ducting to run hot air from an engine to the passenger compartment in a classic Daf car, seemed a bit expensive at the time but not now !! still looks as good as the day it was fitted UPDATE (NEW PURCHASES) Got stuck big time at the weekend when my fuel pump failed (NOT bought from CBS). ordered online as was local and went in to pick it up first thing, lad behind counter was super helpful and although they had literally just opened (saturday morning) immediately ran and picked the parts for my order.. yet again 10 out of 10 thank you CBS

Mistaken Critter

10 months ago

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Visited a couple of times for parts for my kit car, great service, always happy to help, great selection of parts

Devlin Rawlings

11 months ago

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Made an order this morning at 7:45am was already posted by just past 8am

George

a year ago

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If you’re building a car, it’s the place to go!

Ivan Coppins

a year ago

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Endless resources for the needy.

Y. R.

a year ago

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Mit Expressversand schon am nächsten Tag das Paket erhalten! Versand von Großbritannien nach Deutschland. So schnell hätte ich es trotz Expressversand nicht erwartet. Auch am Telefon sehr nette Infos bekommen.

Jessica Billington

a year ago

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Sent by the heavens I think

Mike Hovard

a year ago

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Excellent online shop for a wide range of automotive parts..

nigel clark

a year ago

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Everything I order from CBS turns up the following day, their product range is extensive and prices keen, what is not to like? Excellent service

James Swindell

a year ago

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I looked for parts on Car Builder Solutions web site and found exactly what I was looking for. The parts arrived within 2 days of ordering. Very impressed.

Graham Oliver

a year ago

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Fast and efficient delivery. Highly recommended!

Mark Brunt

a year ago

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first class service

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