this is perfect for 20-30amp escs ,DJI naza lite led and pmu (older version), fpv transmitter (tried on 200mw boscam) , minimum INTERNAL shrink diameter is (round - 1.2cm , flat - 1.9cm) . hope this helps.
I was able to fit it on USB-hub and USB-modem (without a body of course). I use turnigy ESC so can't answer exactly. But you can stretch it a little with pliers inside or something like that. I did that for too thick connector and it worked. So you can buythis tube if you can't find transparent one with larger diameter.