Mountain Bike Tire Bell flat Defense technology provides a protective layer with increased strength and extra puncture resistance Mountain bike tires feature a new optimized tread pattern for your off road adventures A carbon steel BEAD allows the tire to be folded without damage for easy storage Features . Flat defense provides more strength and extra puncture resistance. New optimized tread pattern. Carbon steel bead allows tire to be folded without damage for easy storage Specifications . Size 24 in