/diy/ - Do It Yourself

Why aren't "4 foot" fluorescent light bulbs actually 4 feet?

I thought they were all just "four feet" but I measured all mine and they vary from 45 15/16" to 46 3/4". None of them are even close to a full 48" even including the prongs.

I don't even know how all the bulbs I've purchased in the past work, they're all different lengths. They should be falling out of fixtures. I don't know how I never noticed this for 30 years.

I feel I'd look an idiot if I walked into the store with six different length "four foot" bulbs under my arm, but how do I know which to buy?

Why aren't "4 foot" fluorescent light bulbs actually 4 feet?

I thought they were all just "four feet" but I measured all mine and they vary from 45 15/16" to 46 3/4". None of them are even close to a full 48" even including the prongs.

I don't even know how all the bulbs I've purchased in the past work, they're all different lengths. They should be falling out of fixtures. I don't know how I never noticed this for 30 years.

I feel I'd look an idiot if I walked into the store with six different length "four foot" bulbs under my arm, but how do I know which to buy?