Must Tefillin straps (retzuot) be black, and on which side?

Tzitzit & TefillinTefillin Straps

Synopsis

It is a Halacha l'Moshe miSinai that the outside of Tefillin straps must be black. The inside may be any color except red. The Rambam requires the inside to also be black, but this is not the accepted practice.

Rishonim
Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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