These are a great idea if you have a wedding coming up. They are very sticky and aren't going anywhere once applied. The packaging with this particular company could use an update as the hard plastic purse it comes in is horrible - it's permanently bent making getting the product out a big pain (the zipper breaks in the process), and it dents the bra too. I give this product, from this seller, 4 stars for three reasons - #1- Bad Packaging, #2- The bra silicone is not even and there are some thin areas/dents in the bra (likely related to issue #1), #3- No visual instructions which could be why people who order these think they run small.
Based on reviews of the product being too small, not the case, I'm a 34B and ordered the C regular thickness based on reviews and it's a little big depending on how you plan to wear them. I recommend ordering your actual bra size if you're NOT looking for "lift" or you'll end up with extra silicone pulling skin where it shouldn't. However, out you're wanting lift order a size up because once applied at an angle and clipped together they fit great! Also, get double thickness if you don't want your areola/nipple seen, the normal thickness is pretty transparent.
Instructions, again these should be applied at an angle and not flat directly under the breast if you want lift. They are a great "bra product" that I'd buy again, I just hope the seller changes the packaging it comes in. Please refer to images.