Don't even try to measure your insole, you´ll never get it right. Just look at the measurements on any of your sneakers in CM or CHN. Then take that information and find the corresponding US size in the size guide. For example, the insole length of 25 CM corresponds to US 7 in Vans. You may get a different US size with a different brand due to slightly different measuring.
The Under Armour brand was created with a simple plan to create a better t-shirt. A T-shirt that cooperates with your body to control temperature and increase performance. Under Armor was founded by University of Maryland football player Kevin Plank in 1996. They use technologies like HeatGear® when it's hot, ColdGear® when it's cold and AllSeasonGear®, which you can wear between extreme temperatures. Under Armour have the mission to make all athletes better through passion, design, and relentless drive for innovation.