This model is the back end of the Quad Lock mount

take the file, convert to object and add to any of your models to give you instant Quad Lock capability

I have merged this model into a mount for my motorcycle handlebars, a tank mount, a bicycle mount, even a dog harness mount. you can mount to a flat plate with loops for a strap, or whatever you fancy. nut can be added mid print, or leave a hole to drop the nut through the model

saves me redesigning the same part over and over

simply mount Quad Lock head on top and insert the bolt and nut and your good to go

Fusion 360 example:

in click INSERT → Insert Mesh

Then switch to MESH on the top menu

OPTIONAL - you can then use reduce to reduce the number of faces on the object if you desire

Then click MODIFY → Convert Mesh → OK

This produces an object that you can add to your model. there may be a different way, but ive only been using Fusion for a year or so, and this is the way I know

Have fun creating