Abstract: A wall installation connection box unit, including a box housing body having a rear-side base portion and a sleeve portion projecting forward from the base portion, which sleeve portion peripherally surrounds an installation component mounting space, which space is accessible via an open front end face of the sleeve portion, an extension sleeve which is configured for coaxial arrangement on the sleeve portion and axial pushing back relative to the sleeve portion, and a retaining structure which allows axial pushing back of the extension sleeve on the sleeve portion from a mounting position to an end use position on variable axial level and retains the extension sleeve in the end use position on the sleeve portion.

Abstract: A sanitary wall installation connection box unit, including a box housing body having a rear-side base portion and a sleeve portion projecting to the front from the base portion, which sleeve portion peripherally surrounds a sanitary component mounting space, which space is accessible via an open front end face of the sleeve portion, and a connector body disposed on the base portion of the box housing body, which connector body includes a sanitary component connection contour facing the sanitary component mounting space, a fluid line connection interface structure accessible on an outer side of the box housing body, a fluid conduit structure for fluid connection of the fluid line connection interface structure to the sanitary component connection contour and at least one electric line feed-through opening leading from an outer side of the connector body through the connector body to the sanitary component mounting space.