Exemplary substrate processing systems may include a transfer region housing defining an internal volume. A sidewall of the transfer region housing may define a sealable access for providing and receiving substrates. The systems may include a plurality of substrate supports disposed within the transfer region. The systems may also include a transfer apparatus having a central hub including a first shaft and a second shaft concentric with and counter-rotatable to the first shaft. The transfer apparatus may include a first end effector coupled with the first shaft. The first end effector may include a plurality of first arms. The transfer apparatus may also include a second end effector coupled with the second shaft. The second end effector may include a plurality of second arms having a number of second arms equal to the number of first arms of the first end effector.