Paying close attention to the photo - measure your bike and write down the following;
A - Centre of crank spindle to the top of the saddle (best to take this from the non-drive side)
B - Tip of the saddle to the centre of the handlebars (if you have a short nosed saddle i.e. Specialized Mimic please indicate in Other Info section)
C - Centre of handlebars/stem to the centre of the wheel