A surface extension can be made from the cover of a box where the cover is designed so it is unlikely to fall off or be removed if its securing means becomes loose. The wiring method shall be for an approved length that permits removal of the cover and provide access to the box interior, and arranged so that any grounding continuity is independent of the connection between the box and cove

flexible

Explanation:

A surface extension can be made from the cover of a box if the cover is designed so it’s unlikely to fall off if the mounting screws become loose. The surface extension wiring method must be flexible to permit the removal of the cover and provide access to the box interior, and equipment grounding continuity must be independent of the connection between the box and the cover.

A surface extension can be made from the cover of a box where the cover is designed so it is unlikely to fall off or be removed if its securing means becomes loose. The wiring method shall be made for an approved length that permits removal of the cover and provide access to the box interior, and arranged so that any grounding continuity is independent of the connection between the box and cove

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