I bought a testing kit - the Tee2 - and have been using the greenish lancets which came with it, with the device set to 2. I have now looked at the box of lancets which I bought at the same time, from the same source, and they are blue, and when placed in the stabber, I had to turn it up to 7 to draw blood. The box shows the pin to be 0.31mm - the ones on the greenish lancets are about double that length. I had assumed that the lancets were a set length - obviously not. I decided to post this in the general section, just to reach more people - had I mixed the different lancets I could have found it rather a shock to get a greenish lancet and the device set at 7 after using the blue ones.