The cart, which Amazon unveiled on Tuesday, uses cameras, sensors and a scale to automatically detect what shoppers drop in. It keeps a tally and then charges their Amazon account when they leave the store. No cashier is needed.

It's the latest attempt by Amazon to shake up the supermarket industry and offer a solution to long checkout lines. The online shopping giant opened a cashier-less supermarket in Seattle that uses cameras and sensors in the ceiling to track what shoppers grab and charge them as they leave. Amazon.com Inc. also has roughly 25 cashier-less convenience stores with similar technology.