EPR, EPL, or just shelf labels, are electronic labels that display the price of the product. Electronic Shelf Price (ESP) tags are the new icon of retail technology. Smart, fast, and completely customizable, these ingenious products allow retailers to enhance their shoppers' shopping experience by providing them with information relevant to their purchase. Electronic shelf labels (ESLs) are devices that use electronic ink displays to display retail prices, product information, and other information. They are a viable alternative or supplement to the traditional paper price tags used in many stores today. ESLs can be easily updated by wirelessly transmitting new data, which can include promotions, inventory levels, and special offers, among other things.