A sample from the products for the Rear Cylinder Head (model K9) include: Washer(9.5x20x1), Bolt, Plug,spark(x24esr-u), Cushion.
The most reasonably priced component used on the Vz800 Boulevard M50 2005 (k5) Usa (e03) Boulevardm50 Boulevard-m Rear Cylinder Head (model K9) is the Bolt(6x50).
With five applications this Bolt is the most specified part.