Typically 90mm , providing a significant aerodynamic advantage over standard shallow rims.
Often used as the "baseline" in wind tunnel or real-world testing to measure improvements from other gear. Comparative Speed: 90mm Deep RAR: ~44.5 kph 2-Spoke Wheels: ~44.7 kph Ultron 2-Spoke: ~44.8 kph 📊 Key Testing Insights
Historically, the term has appeared in older database links for compressed music or media files (e.g., deep.rar ).