My friend has a sampling tube (C&L) calibrated for 19# injectors. I am thinking about buying it, but I don't know if I should or not. Later on if I wanted to, could I send it to C&L and get it recalibrated for 24#'s? Or do I have to buy a new sampling tube?
With the c+l meters, you physically change the sampling tube yourself. You would need the blue tube as stated above. Put it in, then your meter is cal'd for 24's.
You don't need to send it in, just change to the correct tube.