received item but coupler isn't centered well and then blade isn't centered. then all vibrates a lot and the cut is much wider than thickness of blade. I did send a message to seller but didn't respond.
great product, good quality. The disc has an inner diameter of 20 mm, the holder has a diameter of 16 mm. The package contains a reduction of 20x16mm. You can buy a disc for 16mm or 20mm.