Bathtub Knob Covers

I've never heard of such a thing.
I think Mom sitting there watching the kid in the tub IS the "cover".

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How old is the child? Does the child need to have access to the bathroom? How about a doorknob cover for the BATHROOM door to keep the child out of the bathroom?

Give us more details about why you need the knob covers, and the age of the child (and other children) and we can help you more.

what kind of knobs are they? Can you just get the generic knob covers for doorknobs and put them on?

I have this same problem with are bathtub. They are more like handles then round knobs. I just unscrew them after running the bath everytime. Never could find anything for babyproofing.