Today I paid £4-49 for a pair of these hideous things. They are made of fairly rigid plastic, stick out so far they catch the back of the baby's throat and make her gag, and encourage her to suck rather than lap at my breast in the usual way. They dull the contact with the baby so neither of you feels the same closeness. And they need to be sterilised - and given I don't own a steriliser of any sort, that meant cold water sterilising tablets which leave a yucky aftertaste of bleach. On the plus side, they mean I can try to allow my cracked nipple to heal while still breastfeeding but I sure wouldn't recommend them except to protect sore nipples.