CHROME TRICYCLE CONVERSION KIT 5/8" AXLE HOLLOW HUB WHEELS for 12" or 16" BIKES | eBay
Amazon.com : Black Trike Conversion Kit for 20 inch Bicycle. Comes with Two 20 inch Hollow-Hub Steel Wheel 36 Spoke. Tricycle, Trike, Three-Wheel Bike Conversion kit : Sports & Outdoors
Trybike - Trybike steel, Vintage trike kit - Little Zebra