We ship our unfinished treads pre-sanded and stain ready and recommend sanding with at least a 120# paper prior to staining or finishing to remove any dust and debris that may accumulate during shipping.
There are several different products on the market that can be used for finishing any of our unfinished treads. Select the one you are most comfortable using and be sure to follow any manufacturer's recommendations for that particular product. We recommend using a finish rated for flooring for added durability such as a Bona-Kemi or other professional grade products. In the end, expect to apply 4-5 coats of finish with a light sanding between each coat.
If you would rather have a tread that already has the clear-coat applied and is ready for installation, consider our prefinished Maple 48" tread:
http://www.stair-treads.com/white-hard-maple-natural-retro-stair-tread-closed-48-in.html