A story...

...In which Justus learns something useful:
Last summer San bought a large blow-up wading pool. For the grandchildren.
It's fine, and the kids loved it, but inflation is time-consuming and a bit tricky. As one might expect, it takes a lot of air.
So last summer I thought, "I'll just use my shop vac". The big one, the one that actually works and that I use for cleaning the workshop and also, when that was necessary, for unflooding the basement. Turns out it sucks really well, but doesn't blow worth shit.
Happily, I had an old one, on its last legs, which no longer sucked much, but blew long enough to inflate the pool.
As I  said, the kids loved it, and consequently, so did we.
That was last summer, and this winter I did a cleanup. The old vac was one of the casualties, because I'd forgotten why I still had it but remembered it was nearly dead.
So we arrive at this year. San and various grandchildren would like the pool up. My shop vac still isn't adequate and our house vacuums don't blow.
But, I remembered, somewhere we have an inflation pump, for the large air mattress we used to go camping to Ontario which we no longer have because it sprang one too many leaks.
I found it: 12V; I got a pump that plugs into the car.
I couldn't see how I could get the car close enough to the pool.
So, I reasoned, there must be a transformer available that would do the trick. And there was, AC to DC, available at Canadian Tire.
So I bought it, brought it home, and plugged the pump in. It ran, but barely. Not nearly enough to inflate the pool.
Off to the internet, to discover that, while the output of my new transformer was 12volts, 2amps, the car's output is 12 volts, 15amps.
So I maneuvered the car down to near the pool, nearly taking out the bird feeder, and inflated the pool.
And resolved never to try that again.
Instead, I ordered the correct transformer, worth considerably more, from Amazon.
It arrived today, and works exactly as advertised.
Anyone want a spare AC to DC transformer in perfect working order, for free?