Costco Cart Tray - M3 Screw Remix

Original Description: If you love shopping at Costco, you'll appreciate this 3D-printed shopping cart tray. It's designed to securely clip onto the newer Costco shopping carts (cart measurements taken in northern California) and give you a space to set down your Costco hotdog, soft drink and free samples. In addition to the tray and cup holder, there's a space for an alligator clip to hold your Costco membership card, receipt or shopping list. Note: This is my own design but was originally inspired by TheIdeaDad. Many thanks to him for the clever idea and giving his OK to share my iteration. I purchased “Metal Wire Alligator Clamp Long-Tailed Alligator Iron Clip Clasp for DIY Card Clip Holder 6 inch (150mm)” from Amazon. I used super glue (cyanoacrylate) to attach the phone holder to the tray.