Helps you decide when it's time to change the chain - if your wear is above 0.5 (10, 11,12-speed) or 0.75 (7/8/9-speed) it's time for a new chain! You can run single speed or IGH chains to ~1.0 wear.

• Drop-in style gauge
• Laser cut CC-4 accurately measures a long section of chain
• Strategically comes in contact with the chain in three places
• Compatible with 5-12 speed derailleur chains (including SRAM AXS)
• Designed to accurately indicate when a chain reaches .5% (10-12 speed) and .75% wear (5-9 speed) and need to be replaced