My 20 year old homebrew bulk eraser uses 4 UVP Lamp #34 0003 0 (germicidal UV lamps) with 4 Ultraviolet Products Inc. CAT L48 ballast 4, 6, or 8 watt 0.16Amp 118V 60Hz (germincidal UV ballasts). New bulbs and ballasts erase EPROMS 1" away from tube in less than 20min. Old tubes and ballasts take 40-60min.