This is a great little mod. I used it with my FHD modded x230. I like to unify my charging cables and this truly helps. Mike mentioned that the cable is a little long and it was a little fiddle to make it fit but it works fine. I will by it again for my t450s.
This has already proved useful. Instead of testing cables for >0.5A capability by plugging in my 20AH battery and seeing whether or not it charges overnight, I can throw away the totally bad ones and use the low-current ones only where appropriate. I didn't look at separate documentation because the labels on the device are self-explanatory.