I had such high hopes for these pacifiers as my daughter uses the evenflow bottles and the shape of these are very similar. These pacifiers are not the cheapest but I thought if they worked, it was fine. Unfortunately, my daughter hated them. The material is very thin and flexible. Nothing like other pacifiers or bottles. I was not expecting them to feel that way. It folds in on itself and my daughter cried and cried when I tried them with her. I had never seen her so upset… I was so excited for these but unfortunately spent $50 for nothing.