This rim is built specifically for the rigorous demand a unicycle puts on a rim. Its the same rim as the double walled eyeletted alloy rim with machined sidewalls used on the Nimbus 29" Mountain and Road Unicycle.
Should you want to build the wheel, here is a link to the Spoke Calculator so you can find the correct spoke length you need.
Spoke Holes: 36
Material: High Quality 6061 heat treated aluminum with box section
Finish: Black anodizing with a braking surface
Nipple Eyelets: Stainless Steel