OK, it works! My first impression was OMG, my abs was shaking like hell without my control.
I will keep use Coreflex till I get 6 packs lol. I put it on to my shoulder as well. Also thigh area. It is easy to use. 6 different mode I used mode 1 for the first time then 2 ended with 3. This come with a usb cable to charge the main device. Super easy. Good for the price!