Patent ID: 7293494

Claim:
A hydraulic valve stack for a machine, comprising: a base having a first mounting surface with a first set of mounting structures and a second mounting surface with a second set of mounting structures, the first set of mounting structures being spaced away from the second set of mounting structures, the base being connectable to the work machine and having at least one fluid passageway extending through the base from the first mounting surface to the second mounting surface, the first mounting surface including an inlet configured to provide the only fluid communication from a pressurized source to valves mounted on the second mounting surface; a permanent valve assembly configured to control a permanent function of the work machine, being connectable to the first mounting surface of the base, and having at least one fluid passageway in communication with the at least one fluid passageway of the base; and an optional valve assembly configured to control an optional function of the work machine, being connectable to the second mounting surface of the base, and having at least one fluid passageway in communication with the at least one fluid passageway of the base.