Welch Allyn Ophthalmoscope Bulb 2.4 Volt Replacement Bulb for Welch Allyn Ophthalmoscope Bulb #04400 Volts: 2.4 Watts: N/A Type: Halogen Length 20 MM Shape: T2 Average Life Hours: 20 Fits Models: Welch Allyn • 11400 • 11411 • 11470 • 11475 • Each line represents 0.125 of an inch. • This chart is to be used as a guide only. • Sizing chart enlarged to show detail.