Chrome Trike Conversion Kit for 16 inch Bicycle. Comes with Two 16 inch Hollow-Hub Wheel 72 Spoke. Tricycle, Trike, three-wheel bike conversion kit - Walmart.com
L-faster 350W Brushed Geared Motor Electric Tricycle Conversion Kit Max Speed 20kph For Small Trike 3-Wheel Bicycle - AliExpress
Trybike - Trybike Steel Trike Kit - The Perfect Ride for Little Ones - Little Zebra
Amazon.com : Chrome Trike Conversion Kit for 20 inch Bicycle. Comes with Two 20 inch Hollow-Hub Steel Wheel 144 Spoke. Tricycle, Trike, Three-Wheel Bike Conversion kit : Sports & Outdoors