Silicone SS size nipple for baby bottles. - Size: SS - Material: Silicone Thank you for viewing. This is an SS size nipple that came with a Pigeon breast pump, but I never used it because I was using other nipples. It has been taken out of the bag, so would it be okay for those who don't mind? When shipping, I plan to flatten the nipple part to make it compact (3rd photo). Please understand that this item has been stored at home.