Ride Engineering keeps your dirt bike running straight and your chain tight with their trick axle blocks. The Ride Engineering Axle Blocks are constructed out of billet aluminum for lightweight durability. Coming in at 6 mm longer then stock reduces your dirt bike from "rocking" by keeping the chain adjustment bolts less extended. Ride Engineering includes two M8 hex nuts to "double lock" your dirt bike's adjusting nuts, keeping them nice and snug. Finishing off the axle blocks with durable anodizing puts a little flash to your swingarm. Sold as a pair. Detailed Specifications: These new precision machined billet axle blocks utilize a YZ250 axle (P/N: MX-AXL22-KT - required) allowing the left axle block to float similar to the Japanese design. The Japanese axle which is forged also provides a little more flex that the stock axle which is just a pipe with threads on each end.