I looked for replacement brush heads for my Sonicare electric toothbrush recently only to find the model no longer sold and placement brushes unavailable. One online retailer had a stash for $36 a pair, with a warning the price may go up $10 when those run out.
My first electric toothbrush was from Interplak. When they came out with a new model and replacement brushes were hard to find, I ordered a dozen pair direct from the manufacturer.
Luckily, I read the label on some Sonicare replacement heads at the store and they said these new replacements are compatible with the old handle, so I bought a few.
I try to be careful with goods I buy. I have a moonroof on my Hyundai that I opened and closed a few times on request when driving some neighbor kids somewhere when I lived in Portland. Haven't opened it since.
I guess in the back of my mind I think about the Volkswagen canvas top convertible I had years ago. An early model with an oval-shaped rear window but the first year they had flashing light turn indicators.
The canvas must have gotten weathered over time. One day as I was driving the canvas ripped and was flapping behind me like Superman's cape. I guess I realize with my Hyundai as with all mechanical things, the top could be stuck open and unable to close. I would hate to say "What?! Again!??"