They have you sit on a stair with a little pad under your butt, (you sit on the lowest stair with you knees kinda high so your sit bones stick out) and after a couple minutes your sit bones leave little indentations in the pad. Then he measured how far apart my bones were and and found a seat where the pads were the same distance apart. It is different from my other seat because it is not so cushy. The cushy seat was so big that it was putting pressure on areas and that you don't want pressure on, and also the backs on my legs, (thighs?). This new one lets me peddle without restriction, so everyplace has just the right amount of cushion.

It is a mens Specialized Avatar 143 seat. Also with a cut-out in the middle. 18.5 is the most miles I have put on it, so I hope it is as comfy when I can do a few more miles!