Ratcheting Spinner
This is a 1-way ratcheting spinner.
Print male & female model.
On the male model, the ratcheting mechanism will be fused to it's bottom after print and will need to be knocked free. There are 5 holes at the bottom. Put a small screw driver in and slowly knock it lose until it can turn. Center hole can be used to push the connections in for a tight fit between male/female knobs.