The HKK Vertex Blue is one of the toughest track racing chains in existence.

This chain is black, but appears to shine blue from certain angles. This is an eye-catching side-effect of the hardening process that the chain goes through during production.

This chain is NJS approved for use in Japanese pro Keirin racing. It's one of the most popular chains amongst pro Keirin riders.

Beautifully finished, super-tough race chain, with small NJS stamps on the chain links. This chain uses a bolt/nut quick-link system, like all NJS certified chains. However, you can alternatively choose to cut and install it with a chain cutter.

Specifications:

• Size: 1/2" x 1/8"
• 106 Links (including Bolt & Nut-type connector link)
• NJS stamped
• Made in Japan

Photo Credit: Cycle Project Store