For Reesibi branded battery powered air duster/blower but may apply for others as well. Bayonet opening diameter is 24 mm and the peg is 4 mm.
Few examples are included if you don't have Fusion 360 installed.
If a projection breaks on the angled component just right click on the sketch and select “Manage lost projections”, select “Edge 1”, click “Re-Link” and select the outer ring on the tip.
The author marked this model as their own original creation.