Cleaning kitten bottles

Anyone found something better than the little bottle brushes that come with nursing kits for cleaning kitten bottles? I find those to be pretty useless as they're so stiff, all they really do is kind of scratch around the inside of the bottle. Kitten formula has a decent amount of fat in it and it tends to coat the inside of the bottle. I bought these:, but they're too big to fit inside the bottles. I took the smallest one and trimmed down the top portion, and it works fairly well, but I don't think it's going to last long. I think something with kind of a spongy texture and slightly flexible handle would be ideal, but I haven't found the right tool just yet.

OMG I'm not the only one who thinks those brushes suck! I personally boil my bottles. I also use baby safe bottle soap when cleaning with the brush before I boil then scrub once more

Try something like this: http://www.containerstore.com/s/kit...ttle-cleaning-sponges/123d?productId=10035726

I found a bottle brush that works really well for the kitten bottles - the length is total overkill, especially since they only had the 16-inch length in stock when I ordered, but I just tried it out and it works great. It just fits into the bottle opening, and its fluffy enough so that the soft bristles really swipe around the sides instead of just scratching at it.