Title is quite self-explanatory. It's a simple round file head. The hole that accepts the file is 3.5mm but at least most chainsaw files have conical ends so it will fit many sizes. In the images i used 4.8mm file and the hole was 2.8mm. It was a bit too small so i enlarged it before uploading here.
Since the hole is not conical i'd recommend heating up the file head before inserting so it will make a perfect fit for itself.
Material i used is PETG but PLA would work just fine if it's not going to be kept in hot environment.
The author marked this model as their own original creation.