These are typically lighting mounts which are flush with the ceiling for the single purpose of giving light Straight Down.
Recessed downlights are generally positioned 1.5 to 2 ft. away from walls with a space of 3 to 4 feet between each light. Dividing the ceiling height by two is a way of gauging how much space to leave between each downlight. Thus, if your ceiling is 8 foot high, place your lights 4 feet apart.
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