Abstract: Various arrangements of carrier trays and carriers for data storage devices, such as disk drives, are disclosed. The carrier trays and carriers have air flow holes that are carefully arranged to promote good air flow across the data storage devices. In one example, the air holes in a tray are arranged so that, when a data storage device is received on the tray, air passing over a first surface of the base from the forward end can pass through the base, over a part of a second surface and back through the base to flow across the recess typically located under the data storage device.