Item description for AMAT Applied Materials Lot of NEW UHV Clean Parts 0021-18623 x4 0021-18626 x1

NEW Lot of 5 Applied Materials - AMAT UHV Clean Parts

Qty 4 - 0021-18623 (one has been opened) - Some kind of a mount or bearing sleeve
Qty 1 - 0021-18626 - Not sure what it is. Possible linear bearing??

There are a total of 5 parts in the lot. One of the parts has been opened, the other four are still sealed. All are new/unused.