I don't know. I was trying to blame it on something but if it was wet or cold it wasn't much. I screwed the top on with my left hand, grabbed the neck with my left hand to put it away and the next thing I know I'm catching it with my right. And it's been my legs twitching and bothering me most and no weakness there yet. So my hand? I'm am scared again and I was doing ok. Nerve conduction all was good now I wait a week for emg