464. What Garments Require Tzitzis?
Tzitzis 3:1
In order to require tzitzis according to Torah obligation, a garment must have four or more corners, it must be large enough to cover the head and most of the body of a child who can walk on his own in the marketplace without needing someone to supervise him, and it must be made of either pure wool or pure linen.
Tzitzis 3:2
Garments of other materials, like silk, cotton, camel’s wool, rabbit’s wool, goat’s wool, etc. require tzitzis under rabbinic law, in order to demonstrate the mitzvah of tzitzis. Such garments only require tzitzis when they have four or more corners and meet the minimum measurements described above. This is because all the garments mentioned in the Torah without elaboration are made of either pure wool or pure linen.