This is an old Suntour freewheel remover tool for 4-prong freewheels! How to use: If used as is, it may come off and break when force is applied, so clamp it with a quick release or hub nut, and then use a wrench to remove the freewheel. (Not a genuine product) I also have a 2-prong type! Please check my other listings! Inner diameter of the prong section: approx. φ20.0, outer diameter φ24.0 The hexagonal section for operation is 23.7mm (approx. 24), hole diameter φ10 Please understand that I will not negotiate a price reduction for this item alone. I will consider discounts for combined purchases or purchases with other items, so please comment. Please purchase without comment unless you are in a hurry. (Shipping may be delayed by more than a week due to long holidays or business trips; if you are short on time, please be sure to contact me in advance to confirm the delivery date.)