Training tools for the grip you actually use.
BamBum designs, prototypes and produces smart athletic hardware and software that solve real performance bottlenecks. Two products, one goal: stronger, safer climbing.
Sloper King™
Train the strength that hangboards forget.
An ultra-lightweight (<100g), biomechanically engineered sloper with 5 cantilever angles. Train the 4 forearm and wrist muscles that a hangboard skips.
- Single unit or complete pair
- 800kg load cord, 5 difficulty angles
- Made in Belgium
Tailr Edge
Every finger, its share.
Made to your fingers, kind to your pulleys. Enter your finger lengths, see the result in 3D and get an edge that loads all four fingers evenly.
- 3D-printed from your finger lengths
- Open drag position, minimal load on A2
- Free STL & STEP files to print yourself
Built in the workshop, tested on the wall.
From a 3D-printed prototype to a tool you can train with: watch how both products are designed, tested and used.

Inventor, engineer and World Cup athlete.
Fré designs every BamBum product personally, with a PhD in Mechanical Engineering from KU Leuven and years of competing at the highest level. Every product starts as a problem Fré ran into while training.
Two products, one approach
Engineered, not guessed
Both products are designed by Fré Leys (PhD. in Mechanical Engineering), who specialises in the mechanics of biological systems.
Built for your fingers and forearms
Smart athletic hardware that solves a real performance bottleneck, from open slopers to unequal finger lengths.
Made in Belgium
Locally produced and dispatched with Track & Trace. Free local pickup in Leuven for Sloper King™.
Backed by a World Cup athlete
Fré is a 2x IFSC Para Climbing World Cup gold medalist. Your purchase supports the road to the LA 2028 Paralympics.
Questions, gyms or coaches?
Want a Sloper King™ test-stand in your climbing gym, or have a question about Tailr Edge? Get in touch.
fre@fre2028.la