O-shopping Ring / O-shopping Ring

This is a ring which can be used to weigh and help people to know the price of the goods, it can calculate the total price automatically and rapidly. In so doing, householders will be able to control what they spend monthly and avoid wasting.
When people shopping, they couldn't know the weight of the goods they buy. So they usually find that what they buy is not enough or maybe too much, and waste time to calculate the total price.