I use this all the time since my rotator cuff surgery. I went through my insurance and I got a 1500 unit for $85 a month rental or $459 purchase. this unit has 3 times the features and was less than $****. Told my insurance about it but they said they were out of network...seems like they need a new network. This unit is awesome...4 modes and almost infinite settings and a auto shut off timer. I leave this hooked up all day and turn it on when I need it. Fits in shirt pocket or use with built in belt clip. I would recommend this to my friends and insurance company.....love it nad it reduces the need for ibuprophin or like drugs.