Instruct: Classify an Amazon review into positive or negative sentiment.
Query: Can not clean inside these deep v-shape threads

The top uses very fine threads that can't be cleaned. After 10 minutes with a tooth brush there is still gunk in the threads. I think it gets forced into the deep "V" in the thread when you close the cap. Better bottles use larger shallow round bottom threads. Also the plastic coating is, well plastic. They do look nice and hold up to abuse. And I don't think the gunk in the threads will kill you because you can turn it into sterile gunk if you soak it in bleach. But it looks bad even at arm's length I can see it.