Abstract: The arrangement of test points on an integrated circuit (IC) undergoing testing in a probe station often requires rotation of the IC or the probes when performing a series of tests. A chuck with indexed rotation promotes rapid rotation of the device under test to a new test position and increases the productivity of the probe station. The device under test is mounted on a device mounting member that is affixed to a shaft rotationally mounted in a base. A resilient seal supports the device mounting member and forms a sealed chamber over a substantial part of the area of the device mounting member. Applying vacuum or pressure to the sealed chamber urges the device mounting member and base toward contact. The support provided by the resilient seal over substantial portion of device mounting member's diameter promotes stability and consistent planarity of the device mounting member without regard to the orientation of the shaft to device mounting member.