It's ok
I am a soccer player and runner. I have constantly callus built up. I just can’t keep up. I thought of the use of this product it gets better. I assume I just have too much callus and I am faster by hand. And when I put too much pressure on it, it does not do the job. I agree you have to make sure you have good brand batteries when using this item. Maybe when I use it every day for 30 Minutes it will work for me. But I do not have that time. So only once a week by hand till I find something that works for me.
Rating: 3 stars