AMAX LIGHTING HD128-120AL Electronic Ballast 1-F21T5/1-F26T5/1-F28T5/F35T5 Lamps Comparison Chart: Dimensions 15.00 x 1.69 x 1.19 InchesAdvance FLUOR Ballast,Electronic,Programmed,32W IOP-4PSP32-SC -IUV-2S60-M4-