So when one runs out of batter, pop it back in the recharge case and use the next one. Very similar to the adidas logo on the new NHL jerseys. i’ll start out by saying that i have wide, tender feet and usually need to stretch my shoes before wearing to avoid blisters. Any knit sneaker will not be supportive enough. buying them individually for the new iPhones my family just purchased. It worked well with my large back tire mounted on my RV and kept my bikes from touching the van. I charged it once when I got it and after 5 days it goes on. I bought 2 of these, after I got the first one and heard the sound coming out of that little thing I went right back to my computer and order another one, I am not kidding around here if you put it out of sight and you will think the sound is coming out of an expensive high end speaker you will be impressed like I was. just used other screws to make it work . anywhere from 10 to 20 minutes.