The Tefillin Cases (Batim, singular-Bayit)
It is a Halacha l’Moshe M’Sinai that the Tefillin be made from the processed hide of an animal.  It is customary to use the hide of a Behama Gasa -ox or cow- since it is stronger, more stable and impermeable. Nevertheless, some Tefillin are made from the hide of a Behama Daka – goat or sheep. The reason for using the hide of goats or sheep is that it is less costly.
In Tefillin Hebron, the Batim are made only from the hide of a Behama Gasa, since it lasts throughout the years.

The Tefillin cases are made up of three parts:
1. Ketzitza – the upper portion of the case, where the Parshiot are placed.
2. Titura – The portion covering the bottom of the Tefillin, attached to the Ketzitza and an integral part of it. The source for this is Halacha L’Moshe M’Sinai.
3. Ma’abarta – Between the Ketzitza and Titura there is a space in the form of a sort of bridge, through which we put the strap of the Tefillin.  The source for this is Halacha L’Moshe M’Sinai as well.
The Tefillin case (bayit) is a whole piece of animal hide that has been processed and folded to form the three parts that have been described.
The lower portion of the Titura is sewn to the upper portion with sinews from a kosher animal.

Titura, Ma’abarta, Ketzitza
 “It has been taught: Square Tefillin – this is a law received by Moshe at Sinai.” (Masechet Menahot 35).
One should be very careful that the Tefillin cases be perfectly square. Any defect in the sides, corners or the edges can affect the quality of the Tefillin, or even render them unfit.
At Tefillin Hebron, we are careful to produce Batim that conform to the highest standards of Hiddur: exactly square, without any flaw or defect in the sides or spots where they join.

The color? It is a Mitzvah for the Batim to be black. One should be careful that the color not peel or rub away.
At Tefillin Hebron, the Batim and Retzuot (straps) are colored with quality black ink that keeps the Tefillin black and polished. It is possible to purchase special ink produced by Tefillin Hebron to color areas that have faded or peeled.