Throughout this document, "Tefach" refers to Hand-Breadth[s].
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The Size of the Entity
The general rule is that a garment must be 3 Tefach by 3 Tefach: Rosh HaShanah 13a; Succah 16a
Cloth: 3 square Tefach: Shabbat 76a, 79a, 125a; Succah 17b
Goat-wool: 4 square Tefach: Shabbat 76a, 79a; Succah 17b
Hide: 5 square Tefach: Shabbat 76a, 79a; Succah 17b
Flat wood "Mapatz": 6 square Tefach: Shabbat 76a, 79a; Succah 17b
Communication to cloth of 1 square Tefach, where it was specifically cut to that size: Succah 17b