Permanent markers

Strictly speaking, only normal permanent markers, but no more than you expect to also. That would be ok, but come with just 3 colors covered and it's been a real chance, if only one of the 3 pins fits halfway! To effectively mend scratches, the color has to match, then you can with those pins actually perform small miracles! Thus, it will be really happy with this set in a very few cases - hence only 3 points.
Frankly, most customers it would be quite worthwhile if he could touch up scratches on furniture with such pins! But this would require probably to the 20 pins, because you can not mix the colors logically! That would be my request to the producer! Decades ago, there were useful sets, today no longer.