i’m not quite sure lol cui are the standard implants that they have been using for years so they are very good! but if you pay extra you can get the soft touch or the responsives which are suppose to be of a better quality and have a lower rupture rate and capsular contraction rate. they also come with a lifetime guarantee. the soft touch are suppose to be softer than the cui (although many surgeons say you cant tell the difference but some of the girls who have them on here beg to differ) and the responsives are the softest around. these implants are round, and come in various projections and widths. like low profile, med/high profile and high profile, even extra high which stick out the most. then you have tear drop implants that cost about £1000 more and are more natural in shape, very flat at the top and fuller at the bottom, hope that helps! xx