Brompton Union Jack Valve Caps – Schrader (A/C/G Line)
Fits Line: A-Line, C-Line, G-Line
Your Brompton deserves better than a plastic cap.
Swap the standard valve caps for ones made from carbon and copper. Same fit, far better finish. Two designs to choose from: a full-colour Union Jack or a stealth black-and-white Union Jack. Sold as a pair. 6.6g total. Fits Schrader valves only.
How it works
Unscrew your existing valve caps and screw these on in their place. The carbon body fits a standard Schrader valve — the type used on A Line, C Line and G Line Brompton inner tubes. The copper collar and domed top badge give a clean, finished look that the stock plastic cap simply doesn't have. More durable too — carbon and copper won't crack or discolour the way plastic does over time.
Important: these caps fit Schrader valves only. They do not fit T Line bikes, which use Presta valves as standard. P Line owners should check their valve type before ordering — the P Line ships with Schrader but some owners swap to Presta. A Schrader valve is short and wide with a pin in the centre, like a car tyre valve. A Presta valve is thinner with a long threaded metal stem. Not sure which you have? Send us a message and we'll confirm.
Key features
- Carbon and copper construction — more durable than plastic, won't crack or fade
- Two designs — Union Jack colour or Union Jack black and white
- Sold as a pair — covers both wheels
- Schrader valve fit — standard thread, screws straight on
- Ultralight — 6.6g per pair
Which valve do I have?
A Schrader valve is short and wide with a small pin in the centre — the same type used on car tyres. A Presta valve is thinner with a long threaded metal stem. Most A Line, C Line and G Line Brompton inner tubes use Schrader. T Line always uses Presta. P Line depends on which inner tube is fitted — check before ordering. Still unsure? Send us a message and we'll help you confirm.
Got a question?
Want to check compatibility before ordering? Contact us — we're happy to help.
Specs
| Material | Carbon body, copper collar |
| Weight | 6.6g (pair) |
| Size | approx. 10 × 17mm |
| Designs | Union Jack colour, Union Jack black and white |
| Quantity | 1 pair (2 caps) |
| Valve type | Schrader only — fits A Line, C Line, G Line; not compatible with T Line (Presta); P Line owners please check before ordering |
Why order from Foldrio?
Because we've been in the Brompton accessories world since 2019 — and we stand behind everything we sell.
Every item tested for Brompton compatibility
We don't list a product until we're confident it works. No guesswork, no surprises.
2 year warranty on all products
Our warranty, not the manufacturer's. If something fails, we fix it.
100% money-back guarantee
Not happy? We refund. No questions asked, no forms to fill.
Free worldwide shipping
Always included. No fees at checkout, nothing due on delivery.
Guaranteed delivery
If your order doesn't arrive, we send a free replacement.
Fast support from people who know Brompton
Questions about compatibility, installation or your order — we respond quickly.
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The price you see is the price you pay. No import fees, no customs charges, nothing due on delivery.