[fiveohpatrol]

The C&L sample tube's have a color on one of the ends that correspond to the color injectors you have, which also is how you tell the difference in the injector size.

ie: a red dot on the end of the sample tube corresponds with 30lb injectors.

another thing, i think that some of the stock 19lb sample tube's dont have a color on them at all.

If you would like, I can grab my dial calipers and get you some measurments on my 19lb sample tube to compare with yours.