Most of the Sunday team has been riding guard sprockets for a long time, so it was just a matter of time before they did their own. TheKnox sprocket is made of 7075 aluminum and comes with a full guard on 1 side of the sprocket. Even more important is the fact that it's designed to fit larger chains like half-link chains. It's made super strong and will help you protect your chain from being hit when slipping off a rail or messing up on a crankslide. FEATURES MACHINED OUT OF 7075 ALUMINUM FULL GUARD ON ONE SIDE OF THE SPROCKET DESIGNED TO FIT LARGER CHAINS LIKE HALF-LINK CHAINS THICKNESS: 6mm