
Certificate of
Authenticity
Authenticity




0
Try on
View authenticity certificate
- Upper
- Flyknit
- Released
- 2023
- Colourway
- Black Blue
ReactX Infinity Run 4 Black Racer Blue
ReactX Infinity Run 4 Black Racer Blue
- Upper
- Flyknit
- Released
- 2023
- Colourway
- Black Blue
DELIVERY AND AUTHENTICATION
Includes Authentication Certificate
by Checkcheck global standards
Come see it in person


Culture Note™
Released on 3 August 2023 and part of the ReactX Infinity Run line. This release has a flyknit upper in Black/Anthracite/Racer Blue/White. Black with Racer Blue is the sensible daily trainer colourway, the one you buy when you intend to run in the shoe rather than photograph it. The ReactX Infinity Run 4 sits in the stability leaning end of Nike's cushioned range, built around a wide, supportive platform rather than the tipped forward geometry of a race shoe. It descends from the same institutional obsession that started the company: Bill Bowerman thought American runners deserved lighter and better shoes than they were being sold, which is why Blue Ribbon Sports began importing them in 1964. Six decades on, the daily trainer is where that promise is actually tested, over months of unglamorous mileage rather than one race.
Running: pair with black tights or shorts and a bright top, since a dark shoe in low light means your visibility has to come from above the ankle, and add a reflective band for early starts. Casual: grey sweatpants or dark jeans with a plain jacket, where black and Racer Blue read as neutral enough to pass as everyday footwear. This is your high mileage shoe, for easy days, long runs and commuting rather than track sessions. Size half up from your casual length if you run long, since feet swell over distance. Hand wash only with cool water, mild soap and a soft brush, remove the insole to dry, and never use a machine on foam.
Nike's running credibility comes from the track first, from Steve Prefontaine as the first endorsed track athlete through to sponsored names like Sebastian Coe, Carl Lewis, Michael Johnson and Allyson Felix, but the daily trainer is aimed at the audience Just Do It was written for in 1988, when the first advert featured 80 year old runner Walt Stack. That campaign was named a top five slogan of the twentieth century by Advertising Age and is held in the Smithsonian, and its whole argument was that the person struggling through a Tuesday morning belongs in the story too. A cushioned, stable, dark coloured trainer is that argument as a product.
ReactX is the foam this generation is named for, and it changes the character of the shoe: a thicker, more resilient midsole than a plated racer, tuned for repeated impact rather than for return at speed. The platform is deliberately wide underfoot, particularly through the midfoot and heel, which is what gives the Infinity line its stable feel and its appeal to runners who overpronate. The upper is engineered knit in black with Racer Blue detailing, with a padded, slightly rounded collar that wraps the ankle. A dark upper is forgiving of road spray, which is a real advantage for a winter shoe. Expect weight over speed: this is a shoe built to absorb work, not to feel fast.
- Upper
- Flyknit
- Released
- 2023
- Colourway
- Black Blue
Most asked questions
How we always
Guarantee the best prices?
Luxury marketplace
In luxury marketplaces, prices depend on demand — less popular items sell below retail.
Competition between sellers
Our 5,000+ verified sellers compete with each other, giving you the lowest prices.
Price comparison
We show you price comparisons across sellers so you always get better deals.
Helping sellers, helping you
We help sellers buy smarter inventory, so they can offer you better prices.
Loading…