Hydraulic Hinged Bridge Assist: This design uses a platform installed hydraulic cylinder and power unit to raise the hinged bridge plate to the vertical stored position. To lower the hinged bridge plate the dock attendant first unhooks the stored bridge plate and manually nudges the bridge plate forward. Safe, controlled lowering of the hinged bridge plate is accomplished by a fixed flow control valve that is installed on the power unit. To return the lowered bridge plate to the vertical stored position the dock attendant operates the push button control, the hydraulic cylinder connected to a chain raises the hinged bridge plate to the vertical stored position. The dock attendant then re-connects the chain securing the hinged bridge plate in the raised, stored position. This option eliminates any physical lifting of the bridge plate. This link shows a hydraulic hinged bridge assist. View Page