A.A.U. Four-Wall Rules · American four-wall
Rule 34
HistoricalA.A.U. Four-Wall Rules, 1 January 1920 (historical)
Hands or fingers may be covered, but only with soft material or soft gloves of kid or cloth. No hard material shall be used on any part of either hand.
Mentioned here
How this rule changed
See the wording of this rule in every rulebook, with the changes marked.