A tabular assembly base (2) is proposed, which serves for the detachable fitting of a valve unit (3). The assembly base (2) is modular in design and comprises a plurality of individual base segments (23) joined together as a rigid unit. The valve unit (3) comprises several valve modules (4). Underneath the base segments (23) several connection segments (25) are located which are associated with the valve modules (4). They possess load ducts (33) communicating with the valve modules (4) and having an electrical and/or fluid power functional unit (38) associated with them at least in part.