The X-Fusion O2 Pro R 190x45 rear shock is a high-quality air shock designed for mountain bikes. Made of lightweight aluminium, this shock offers a smooth and controlled ride over rough terrain, you can trust in the durability and performance of this rear shock. A reliable choice for any cyclist looking to upgrade their suspension. A massive upgrade for some full suspension MTB bikes !! I would advise getting new mounting bolts and bushes when changing your suspension. This comes with some spacers and the original bushes. (Spacers never used)