ON RUNNING CLOUD X 4 CASTOR FLAME WOMENS
In stock · Ready for dispatch
Free tracked UK delivery · dispatched within 24/48 hours · arrives in 1–4 business days
Delivery estimate
Free tracked delivery · estimated arrival 5–7 business days
Delivery estimate
Free tracked delivery · estimated arrival 5–10 business days
| UK | EU | US | Foot length |
|---|---|---|---|
| UK 2.5 | 35 | US 4.5 | 21.2 cm |
| UK 3 | 35.5 | US 5 | 21.6 cm |
| UK 3.5 | 36 | US 5.5 | 22.0 cm |
| UK 4 | 36.5 | US 6 | 22.4 cm |
| UK 4.5 | 37.5 | US 6.5 | 22.9 cm |
| UK 5 | 38 | US 7 | 23.3 cm |
| UK 5.5 | 38.5 | US 7.5 | 23.7 cm |
| UK 6 | 40 | US 8.5 | 24.1 cm |
| UK 6.5 | 40.5 | US 9 | 24.6 cm |
| UK 7 | 41 | US 9.5 | 25.0 cm |
| UK 7.5 | 42 | US 10 | 25.4 cm |
| UK 8 | 42.5 | US 10.5 | 25.8 cm |
| UK 8.5 | 43 | US 11 | 26.3 cm |
| UK 9 | 44 | US 11.5 | 26.7 cm |
| UK 9.5 | 44.5 | US 12 | 27.1 cm |
| UK 10 | 45 | US 12.5 | 27.5 cm |
| UK 10.5 | 45.5 | US 13 | 27.9 cm |
| UK 11 | 46 | US 13.5 | 28.4 cm |
| UK 11.5 | 47 | US 14 | 28.8 cm |
| UK 12 | 47.5 | US 14.5 | 29.2 cm |
| UK 12.5 | 48 | US 15 | 29.6 cm |
| UK 13 | 48.5 | US 15.5 | 30.1 cm |
| UK 13.5 | 49 | US 16 | 30.5 cm |
| UK 14 | 49.5 | US 16.5 | 30.9 cm |
| UK 15 | 50.5 | US 17.5 | 31.8 cm |
Conversion shown for On (women’s). All sizes on this page are UK — pick your UK size above. Full size guide ›
- Low stock - 1 item left
BRILLIANT
BRILLIANT SERVICE, AUTHENTIC TRAINERS, FAST DELIVERY. WILL DEFINITELY BE ORDERING FROM PS AGAIN.
Sabiul Hoque
Fantastic service
Fantastic service, next day delivery. The trainers are perfect. Really pleased have used twice for Jordan’s b
Steph Clifford
Impeccable condition, astonishingly fast
Recently purchased a pair of shoes and was thoroughly impressed. The shoes arrived in impeccable condition and the delivery speed was astonishingly fast. Highly recommend!
Marteinn Gunnarsson
Such quick delivery so pleased
Such quick delivery so pleased
Amy Marchant
Verified reviews on Trustpilot from Project Sneakers customers
Verified
Authenticated in-house
Every pair is inspected & verified by our team before it ships.
The Cloud X 4 is ON's refined running shoe, engineered for responsive comfort across road and track. This women's iteration arrives in Castor and Flame—a sophisticated pairing of deep charcoal and vibrant orange that balances understated elegance with visual presence.
Designed for those who demand performance without compromise, the shoe combines ON's signature CloudTec technology with a streamlined aesthetic. The Castor Flame colourway elevates everyday training, offering a versatile option that transitions seamlessly between serious runs and casual wear.
SKU: 3WE30073560
Every pair is brand new and unworn, supplied in its original box. Nothing we sell is used, worn or ex-display — just deadstock, ready to wear.
Every pair is verified 100% authentic in-house before it ships — checked against known-authentic references for materials, stitching, labelling and box details.
Fast UK tracked delivery, with next-day options at checkout. Orders are dispatched securely and double-boxed to protect the shoe box in transit.
Not the perfect fit? Enjoy hassle-free 14-day returns & exchanges. Full details on our Shipping Policy.