it doesnt mean higher the SPA, the better it is... u should see the type of the skin u have. if u have oily skin, it is better to use the a lower SPA like 15... cuz it is kinda thick and oily when the SPA is high. and reapply it every 2-3 hours when u think necessary.. and also remember to look at another component: UV protection...

so try to get those with SPA and UV protection...