lower media, middle media, upper media gen.

[nymph]

Речь идет о роботизированной ячейке. Помогите перевести, пжлст.

The robot will work in conjunction with our multi-media finishing heads. Each
head is arranged so that up to (4) types of media can be used on the same spindle.
The lower media being a 14" diameter brush, the middle media being an 8" diameter brush, and the upper media being a 4" diameter brush.

[nymph]

Нашла ответ, м. б. кому-нибудь пригодится:

lower media, middle media, upper media - грубый, средний и тонкий абразив