C-H:

Re. two-pin Chinese plug:

Welll....yes.

But if you compare the two, the difference is fractions of a millimeter. The "Chinese" version will fit a NEMA outlet and will make proper contact.

I The holes in the pins are optional. According to a NEMA document I found on-line that gives plug-blade dimensions and various configs, they're used for manufacturing purposes (to hang the little pins from a wire or clamp them while molding?)

Loads of stuff gets sold here with that plug. Myself, I have a 110-volt charger for a an electric shaver, a night light and a small glue-gun with that exact plug (with no holes). None of these are UL listed.

I've also seen extension cords with plugs with no holes in the blades and even some very old appliances (American made with American-made cordsets) that also don't have those little holes in the plug pins.

China also uses the Australian-style plug for appliances that require grounding I found out.

As far as the USA requiring UL.....hmmm....well....to be honest....it's optional. [Linked Image]

It's a good MARKETING practice to get a UL symbol (and some places, like do insist on only using/having UL listed devices), but it is not necessary. Otherwise we wouldn't have all these non-UL listed appliances in the USA.

My computer stereo speakers are also not UL listed and these work directly off the 110-volt wall sockets with no "power-pack".

The weird thing is that the speakers are stamped with the CE logo!!! [Linked Image]