- The KMC K1 chain is designed for heavy-duty BMX freestyle and track bikes The K1 chain has an OS outer and tall inner plates which provides the chain with unbeatable tensile strength and eliminates stretching and chain drop. This makes it the perfect chain for high load sports like BMX or Track cycling where you're putting high amounts of pressure on the drivetrain. * 1/2" X 1/8" - 110 Links, pin length 9.5mm * Compatible with: BMX / Freestyle * Nickel Plated/Black Silver * Special Dynamic Configured Plates * Weight: 411g