Label stickers for my work equipment: cost category and professional use percentage?

In my line of work, as a freelancer in the events sector, it is very common for us to label the equipment (cables, flight cases, devices, etc.) that we use and/or offer rental with stickers bearing our company name and logo.
This is not so much for marketing reasons, but mainly to make it easier to find our equipment back among other people’s equipment.

Which cost category should I put this under?
And what professional use percentage can we apply here?