I bought a Welch Allyn otoscope/ ophthalmoscope when I was a lowly medical student in 1980. Recently I had to pull it out of the old shelving. I discovered that the original battery had expired in 1987 !! To my great relief, Welch Allen is still making batteries for their equipment, and to my even greater delight, it is still the same size! My medical bag is back to being functional, even though it's been 40 years since I started it.
