I recently purchased Fanatec's button cap/decal pack and I have to say, it's a very worthwhile, inexpensive, and idiot-proof bit of kit. The customization options are incredibly vast, with ~20,000 possible combinations
Fanatec Button Caps und Sticker Set - ClubSport Steering Wheel BMW GT2 - YouTube
CSL Elite Racing style button caps | Studio-397 Forum
New: Customisable Button Caps! — Fanatec Forum
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Fanatec button caps and stickers | RaceDepartment
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Fanatec ClupSport Magnetic Button Module + Button Caps on the Formula V2 : r/simracing
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Formula Wheel v2 included button sets — Fanatec Forum
Sell - (UK) Fanatec universal racing button caps (from Podium Racing Wheel F1). Brand new, unused. | RaceDepartment
For anyone interested in what you get from Fanatec's button cap/sticker set, here's a quick overview of the contents and the numerous different function labels to choose from. A few friends asked
New: Customisable Button Caps! — Fanatec Forum
ClubSport Steering Wheel Formula V2.5X | Fanatec
Formula V2 button caps — Fanatec Forum
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Fanatec CSL Elite Steering Wheel P1 | Shopee Malaysia
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec
Button Caps and Sticker Set | Steering Wheel Accessories | Accessories | Fanatec