Abstract: An adjustable device to support a seat on a machine or vehicle that is laterally pivotal about an axis parallel to the longitudinal axis of the machine to permit the seat to accommodate uneven terrain. At the will of the operator, this device can be adjusted to a horizontal position, thereby providing comfort and safely when operating a machine on uneven terrain. The device is to provide an improved seat mounting wherein the seat swings from a common point and movement thereof is controlled by an electromechanical linear actuator, activated by a double throw-double pole switch, (voltage determined by equipment manufacturer), located within easy access of operator. Another important object resides in providing a way to secure seat in a fixed horizontal to seat mounting in the event of malfunction or power failure. Spare clevis pins, provided with hair pin clips, could be inserted in pre-drilled holes which will secure seat and movable framework to base assembly parallel to each other.