"Graham." wrote in message
...
What I would like is a through plug, so that I can still connect another
mains device. I find plenty on the net price varying greatly, but non
specify it the 13Amp plug is a "through" one. I hope this makes sense!

Are you sure you need *micro* USB socket(s) on the adapter? That's
most unusual.

The normal convention is to use USB-A (large rectangular plug) on the supply
end, and USB-B, or mini, or micro USB on the appliance end. Devices such as
rechargeable batteries use micro for the power input from a mains adaptor
and USB-A for the output to the phone etc, so you always use an A-to-micro
cable, both for charging the battery from the mains and for charging the
phone from the battery (and for charging the phone directly from the mains).
I've never seen an micro-to-micro cable.