The lacie 5tb 2big thunderbolt and network drawer is a spare drive and drawer for use with the lacie 2big quadra 2big dual 2big network 11 2big network 2 and 2big nas the spare drive and drawer increases security in the unlikely event of a drive failure you can immediately and easily hot swap a failed drive the capacity of your spare drive must be equal to or higher than the capacity of the drive being replaced this drive features a storage capacity of 5tb