Wd my cloud expert series ex4100 24tb 4 bay nas product specifications average latency na average read seek na battery yes cachebuffer na data transfer rate na disk capacity 24tb drive bays 4 interfaces usb 30 x 3 one in front two on the back gigabit ethernet memory 2 gb ddr3 processor arm dual core 16 ghz rotational speed na tape drive na write speed na product dimensions length 913 in 232 mm width 669 in 170 mm height 756 in 192 mm weight 24 tb