Oh. It will be funny to play with the Tria.
The battery runs for 30 mins. Shave and apply the Tria. In the beginning, it will be a little bit painful, and you may lower the power level at which you feel comfortable. I have used it for about 10 months. As time goes, it will not take so much time and pain. Legs take longer time, while armfits less. I usually use the Tria while drying my hairs with a fan after shampooing. For beard, I have treated more than 20 times, but still see some fine hairs. Nowadays I use the highest power level. When I ever try to use it apply to facial areas close to the eyes, I zap while closing my eyes.
And read the user's manual well. I guess I will not be able to completely remove the unwanted hairs, but the Tria can greatly reduce them.
Good luck,
Barbie~~