It has a magnetic flip top that feel like a quick flick would snap it right off. I had to to up to a size 10-11. This works well and requires no intervention other than choosing "connect" from the Bluetooth menu. When I first tried to waist trainer on I was a little shocked because it was my first time wearing a trainer and it was snug to say the least. And then after that, I can turn back on the bluetooth on my phone, and I finally get my beautiful stereo sound, instead of just one speaker connecting. I only gave it 4 stars because I dislike the idea that you have to purchase the expensive pods in order for this device to work. 5 (US womens) and the shoes with full heels I wear a 7. The gogh pro is a real leather upper whereas these patents are lovely and shiny but are man made. The sound quality is amazing! But its moot since the battery is so big.