|IBM Ultra320 SCSI Hot-Swap SSL
There are three types of 3.5-inch metal hot-swap trays used to house
SCSI drives in the majority of IBM xSeries servers. The picture below
shows the difference between them:
This tray has a cutout on the rail which enables its use in servers that
do not use older U320 and U160 trays (such as the x336 and x346). As with
the older U320 tray, this tray also has an elongated stub that prevents it
from being mounted on an Ultra160 bay.