NU1 Pro Downlight by Alphabet Lighting. Small, but mighty. The NU1 Pro Downlight features a 1-inch diameter, making it our smallest downlight yet, with up to 1300 lumens. This option-rich fixture is available in round or square designs and can be configured as a downlight, adjustable, or wall wash. Say bye-bye to glare with our deep regress and other glare control options.