Flanged cylinders have a rolled edge that makes them more comfortable to wear for a longer period. Flared cylinders gives you a puffy areola and pulls the nipples out at the same time. After several weeks you will notice a puffier look and feel to your nipples that wil feel great all the time.
High_Pressure thick cylinders are made to withstand a higher vacuum pressure so you get quicker sessions and much longer nipples.
The High_Pressure Thick cylinders also come with a 5 year no questions asked replacement guarantee.