This type of ring magnet features a conical hole to be used with countersunk screws to get a plane (flush) surface

Sjove magneter formet som små krokodiller

so buy only if it is necessary for you to have hook magnets on your glass board

But you have to know that it is a very strong magnet which means that you have to handle it with caution

Small but strong hook magnet with eyelet hook (closed hook)

Legamaster Board Eraser filt, 10-pak boardmarker mix This type of ring magnetNew felt pads for the white whiteboard eraser from Legamaster. You get a pack of 10 felt pads. There is no need to swap out your entire eraser with a new one when you can just change the felt at the bottom. Colour: Light grey. Art. no.: Legamaster Board Eraser Pad, 1204 00. The felt sheets last a long time, so there is enough for plenty of uses in this 10 pack.