This 4" black alzak is an ideal solution for tight spaces and hard to light areas such as low ceiling, niches, bedrooms, corridors and similar environments. To be used with Lightolier IC New Construction, Non-IC New Construction and Non-IC Remodeling recessed light housing. White trim. Black alzak. Line Voltage. Takes one 50 watt PAR20 bulb (not included). 3 3/4" aperture. If using a Non-IC housing can use a 75 watt PAR16 or R20 light bulb.