How One Bag Fits Every Shopping Cart The founders of Lotus Trolley, a reusable shopping bag system, measured shopping carts across the globe to build a product that would work for all customers.

As eco-minded residents of California, Farzan and Jennifer Dehmoubed were thrilled when the state banned single-use plastic bags in 2016. But soon their home was packed with a new kind of waste: heavy-duty totes that, despite their intended reusability, were often forgotten, susceptible to mold and bacteria, and ultimately destined for the landfill. The couple saw this as an opportunity and created the Lotus Trolley Bag, a compact set of four machine-­washable, mold-resistant grocery bags that hang inside a shopping cart, suspended by rods that help you easily move items from cart to car to home. Then came the big question: What size does it need to be to fit inside most carts?

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The couple thought the answer would be easy; they visited their local grocer, Ralphs, to measure carts. But then they visited Walmart and found ones that were totally different sizes. "We started going to every chain we could to take measurements, pulling up to parking lots with our empty bags like crazy people," Jennifer says. After each visit, they'd tweak their prototype. "We had to consider the widest part of the cart, the narrow part at the front, the depth -- we made a big spreadsheet," Farzan says. They ultimately visited 50 stores across four different states in 40 days, and they enlisted far-flung friends and family to send shopping cart dimensions from across the country.