Small oval : It is  Suitable for that kind of want to full of the middle part of lips, best use with vertical;
 

Middle oval:  It is suitable for the number those mouth relatively small, relatively thin lip;
 

Large round : It is suitable for who wanted to do for a full lips are full of effects, or itself on thicker lips;
 

Gently suck, just a few seconds, immediately change the lip, give you a Super Sexy Lips !  just have one disadvantage, The full lips only last for two hours.