It's designed according to the sole reflexology and traditional chinese medical theory,uses the alkaline battery,the user can enjoy massaging and remove the foot fatigue anytime or anywhere.this product is suitable for these person who stands for a long time or runs in society every day when they are work especially,when you feel tired,you just slightly use foot to press the massager,then it will relax sole and remove fatigue directly.If you want to close it,just lift your foot up.