Backhoes will sometimes come with extra hydraulics but 99% of the time, this is a 1 way valve for a hoe pack or hammer. This will not control a thumb since it needs a 2 way valve. To get hydraulics we install a electric diverter valve that shares the pressure to one of the out rigger cylinders. The user controls and activates the thumb by first toggling a toggle switch that we have mounted. This selects either the out rigger or the thumb. Depending on the selection, the user moves the outrigger to conrols either the thumb or outrigger. If you pick something up with the bucket/thumb and then select the other position of the toggle switch, you still maintain grip/pressure. All of our backhow thumbs are pin based non link. We also build bolt on top cylinder mounts for some extendahoes and those units with Cast dipper sticks.