Don's bulbs rare light bulbs and lamps glossary of terms definition of: /U What is special name suffix "/U"? This special name encoding reference means: Universal burn position. On Metal Halide lamps, means universal operating position (burn any position). Otherwise, on halogen bulbs, "U" is the base type. references for this page: /U, UVS, ULTRA-VIOLET STOP, UNIVERSAL BURN, UNIVERSAL POSITION, UNIVERSAL reference to this page: /UVS