Thanks,
I did check their site before posting of course.
Their page for TH26011AS says "all LCR digital bridges"
https://www.tonghui.com.cn/en/product_698.htmlTH26011BS says "Applicable to: Four-terminal pair instruments such as TH2828, TH2828A, TH2828STH2826, TH2826A can be used with other LCR instruments to obtain better measurement results"
TH26011CS says "Applicable to: TH2830 series, TH2523 series and other LCR instruments except TH2828, TH2838, TH2839 series"
I also wonder if when they say "all LCR digital bridges" it means all of THEIR LCR meters, not necessarily other manufacturers.
unfortunately they do not actually tell you what the difference is, are they wired differently, different bnc spacing ,etc.
I guess I'll have to try and contact them. Reality is I've got to order this from China, so I want it to be right the first time since returns won't be a practical option.