Adaptor, 17 mm or .669" ID x 1.375-24 tpi OD CW - Right Hand Threads x .9" wide, has 6 mm key way and two set screws.
Made for the Schwinn Meridian Trike, Adaptor for freewheel sprocket.
The Schwinn Meridian trike has a 17 mm OD axle with a 6 mm keyway.
Be sure and add the freewheel, 6mm key or any other parts you need to the cart.
Note: You may need to file or sand down the key so it will fit due to the odd 17 mm shaft.
