Genuine Neitz brand L29 bulb. Halogen 2.5W 4V L-29 replacement for the Neitz direct ophthalmoscope BX-12, BX-123, BX-RC, BX-4VH, BX-RP, BX-12, BX-123, BX-RP, BX-RP-RX, BXRCII. 

Lite Source Inc. is an authorized Neitz distributor.