This is, I believe, a replacement freehub body for a Transition Revolution hub. It was acquired along with some other parts from a shop that had gone out of business. It was out of the original packaging, but had a note attached indicating that it is for a Transition Revolution hub. Checking around on the interwebs seems to confirm this, but please ask if you have any quistions. Axle diameter is 15mm. If you need any other information please just ask.

Free local pick up in Seattle, otherwise $5 shipping. Can combine with other items.