Unfortunately I didn't read the full description carefully enough. I thought the 8mm size was the shaft hole. It's not - it's the thickness of the bearing. Shaft bore 10 mm. Guilty. I put them in a storage box for the next project. I'm sure everything will be fine. They are packed in their own plastic bag and packed in an overall carton. We packed. The ones I tested rotated with reasonable resistance. These are not spinner bearings so they don't spin as freely. I would call them standard bearings. If you think this review is helpful to you, please click the 'Useful' button below.