For an aftermarket EBS clutch made as an OE style Polaris primary (aka drive) clutch made specific for 2008-2009 RZR 800 models below. This is the EBS clutch meaning it has a 1 way bearing like what came stock on 2009 RZR 800-S. More on that below. This clutch is made just for RZR unlike other aftermarket ones I have seen. I have spent good amount of time testing and revising these clutches before selling them to make sure they have smooth and responsive performance on RZR 800. I do guarantee this comes correct for ready to bolt on and ride with weights and spring already in it! *This is the EBS style of clutch, meaning it has a one way bearing which adds EBS (engine brake system). This came stock on 2009 RZR 800-S. The 2008-2009 RZR 800 and 800-S have a Tied style secondary with a moderate EBS helix in it. This 1-way EBS type primary goes great with the 2008-2009 RZR 800 stock secondary. The 2010-2014 RZR 800 come with a weaker EBS disposable type clutch called a Rapid Reaction secondary. You can add this next to the 10-14 OEM Rapid Reaction Secondary but EBS gain will be mild or not noticable unless you upgrade your 2010-2014 Rapid Reaction secondary to a Tied style secondary first. I also sell the tied secondary upgrade as well.