Editing Tefillin (section)

===Straps===
Black leather straps (''retsu'ot'') pass through the rear of the base and are used to secure the tefillin onto the body.<ref name="JewishEncyclopedia"/>  The knot of the head-tefillin strap forms the letter ''[[dalet]]'' ({{Script/Hebrew|ד}}) or double ''dalet'' (known as the square-knot) while the strap that is passed through the arm-tefillin is formed into a knot in the shape of the letter ''[[Yodh|yud]]'' ({{Script/Hebrew|י}}). Together with the ''shin'' on the head-tefillin box, these three letters spell ''[[El Shaddai|Shaddai]]'' ({{Script/Hebrew|שדי}}), one of the names of God.<ref name="JewishEncyclopedia"/>

The straps must be black on their outer side, but may be any color except red on their inner side.<ref>Shulchan Aruch Orach Chaim 32:3</ref> A stringent opinion requires them to be black on the inner side too,<ref>Shut Shevet Halevi 9:16</ref> but more commonly the inner side is left the color of leather.

The Talmud specifies that tefillin straps must be long enough to reach one's middle finger, and records the practice of Rav [[Aha bar Jacob]] to tie and then "matleit" (plait? wind three times?) them.<ref>[https://www.sefaria.org.il/Menachot.35b.5?lang=bi&with=all&lang2=en Menachot 35b]</ref> However, the passage leaves unclear where the measuring is done from, whether the reference is to hand- or head-tefillin, and what exactly the meaning of "matleit" is. Combining and interpreting the Talmud's statements, [[Maimonides]], [[Arba'ah Turim|Tur]], and [[Shulchan Aruch]] ruled that the strap of hand-tefillin must reach from where the tefillin is placed on the arm, as far as the middle finger, where it must be wound three times around the middle finger.<ref>[[Mishneh Torah]] Hilchot Tefillin 13:12; Tur Hilchot Tefillin 27:8; [[Shulchan Aruch]] Orach Chaim 27:8</ref> [[Moshe Isserlis|Rema]] wrote that it is not necessary to wind around the finger (rather, the straps must be long enough that one ''could'' wind around the finger);<ref>''Darchei Moshe haKatzar'' Orach Chaim 27 letter 5</ref> however, this leniency does not appear in his comments to the Shulchan Aruch. In addition to the windings around the finger, the Shulchan Aruch states that the custom is to wind six or seven times around the forearm.<ref>[[Shulchan Aruch]] Orach Chaim 27:8</ref>