Racks for operation in a data center, robots for use with racks of a data center, and methods of removing sleds from, and inserting sleds into, racks of a data center are disclosed herein. A rack includes a plurality of sled spaces and a plurality of sleds. Each sled is mounted in a corresponding sled space such that the plurality of sleds are spaced from one another in a vertical direction. A robot is configured to interface with any of the plurality of sleds mounted in the sled spaces.