White nylon plastic with a matte finish and slight grainy feel.
About this Product
Mountain bike chain keeper for 1x9 (or 1x8/1x10) setups. Designed for 31.8 mm seattube mount, 32-36t chainring with 48-51 mm chainline. To install you'll need two M5 nuts and screws. Special version for frames with open front derailleur tube like GT Sensor/Force.
Assembly instructions: http://carrottread.com/index.php?id=ultra_instructions