They look and work great
My theory is every serious mountain biker should ditch the innertubes in their tyres if they haven’t already for better performance.
This means tubeless valve stems are an essential purchase, plus they need to be replaced occasionally as Presta valve heads get damaged or bent too.
Peaty’s valves come with a lifetime replacement warranty against cracking or bending, and also pack the excellent added feature of a dust cap with and oval hole in it that doubles as a valve core remover.
It’s this detail I’ve found useful multiple times (if a pump accidentally unscrews the valve core or you need to top up sealant in a car park), but ten funky colours will doubtless appeal to bike tarts too. They look and work great then, but Peaty’s anodized 7075 aluminium valves with their snazzy O-ring tensioners do cost about £7 or £8 more than other brands.