Kirk,
I have an IMED Gemini PC-2tx and a Hamilton micro lab 900. I have not been able to pinpoint the gauge of tubing for either one. But I did find everything else that anyone could ever want to know about the Imed.
On Monday I will call the companies and try to find out the tubing type and gauge. They are both double pumps for delivering two fluids simultaneously, at different flow rates.
Bill