Your bulbs are energy efficient, but what about your housings? These gasketed, airtight housings keep heated or cooled air from leaking into your ceiling spaces. The steel housings adjust up to 1.75 inches to accommodate shallow ceilings and fit RELED4RT30 lamps. IC rated, the prewired units are designed for mounting in direct contact with insulation materials. Coupled with prewired junction boxes and in packs of six, these housings make swapping out your recessed fixtures simple.