Small but rated at 50 wpc.
Wait a minute... are these functional steam engines?
Here's an old Zippo alongside my latest tiny purchase- a miniature 24/192 DAC- it is really that small! Cost $12 and came with with a 1.5M toslink cable and a 5v 1A PSU.
I'm about to run a bunch of tests on it- it can't be as good as it sounds.
I have the same DAC, I think. Mine is Fiio-branded. Works like a charm. I was surprised too.