So I recently obtained two orphan female kittens at the age of three weeks old. It took care of them, bottle fed them until they were old enough to eat on their own. I was a proud owner of these two beautiful perfectly healthy kittens. I knew that one way or another i wanted to avoid any fleas on the kittens or in my house so in an attempt to do it cheaply in bought two flea collars from hartz at the store. Big mistake. At the time i didnt realize that any flea collars could be dangerous. I have seen them be used before with no problem. The package said it was for kittens 12 weeks or older so when the kittens were twelve weeks old I put the collars on as instructed at about 7pm. At that point i was settling down for the night, watching tv, and about midnight i look over and notice one kitten laying in the middle of the floor with her eyes closed… i noticed it was kind of strange considering they usually slept on the couch or recliners or in my lap all snuggled up. So in attempt for some snuggling i picked her up and set her in my lap. She woke up and that’s when it noticed her swaying back and forth unable to stay still, with drool pouring from her mouth. I then look over to my other kitten and was shocked to find her attempting to walk across the floor but failing as she fell all over the place. At this point in was very concerned, i put them both in a box with some blankets and monitored them… neither could control their body… they swayed back and forth, twitched and spasmed as if having seizures. I removed the collars, rushed them to the vet emergency room where the vet explained the nerve and brain damage may or may not be permanent. The only option was to give baths to wash away any excess chemicals and wait.. so that’s what we did. When it got home i started to research and was horrified by what is found. The chemicals in the flea collar are meant to get into the cat just enough so that if a flea does get on them or bites them, it will attack the fleas nervous system and kill them almost instantly. Instead the chemical attacked the nervous system of the poor kittens. For the next few days i waited terrified, watching my babies convulse, spasm, not be able to walk, eat, drink… having to resort to bottle feeding them milk and water which they hadn’t done in weeks just so they didn’t starve or dehydrate. After about four days it settled down and they eventually started walking again after days of our own personal physical “therapy” which consisted of exercising there stiff weak legs. And using yarn as motivation for their weak attempts. Now they are six months old and healthy as can be.. but it will never forget the horror that they and i went through. Please do not EVER use this product.