I've read the entire manual for the UCR210D, but it doesn't seem to specify anywhere exactly what is the connector for using external power?
As my intention is to build myself four cables (one for each Lectrosonics UCR210D) going from that connection at one end to D-tap male at the other end.
So then I can use them together with this attached to my BP-U60 battery in my bag:
https://www.bhphotovideo.com/c/product/1171544-REG/indipro_tools_rk301_4_way_d_tap_splitter.html
Should work well, yes?