1. May one wear a Tallis inside out?[1]

A Tallis Katan[2] [that has two holes[3] in the corner] is not to be worn inside out.[4] [Regarding a Tallis Gadol, and a Tallis Katan that does not have two holes: Some[5] write against doing so. From other Poskim[6] however it is apparent that there is no need to be careful in this matter. Practically, by Chabad Tzitzis one is to be careful in this matter.[7]]

[1] Siddur Admur “One must to be careful that the Tzitzis be hanging on the upper, external, part of the clothing and not on the inner lower part”

So also rules: Olas Tamid 11:12; Likkutei Maharich in name of Kitzur Shlah; Arizal brought in Shaar Hakavanos Tzitzis 6; Peri Eitz Chaim Tzitzis 1; Nagid Mitzvah.

[2] The simple understanding of Admur ibid is to be referring to a Tallis Katan with two holes. However see Tehila Ledavid 11:8 that learns it refers only to a Tallis Gadol, while by a Tallis Katan [even of two holes] the issue of Reisem Oso does not apply. [See of Rav Raskin on Siddur 83]

[3] However by those with one hole, the reasons brought by Admur do not apply. [Glosses of Rav Raskin on Siddur 83]

[4] The reason: As the verse states “Ureisem Oso” that the Tzitzis must be seen [Admur ibid] and when worn inside out, the inner corner blocks that area of the fringe from visibility. [See Tehila Ledavid 11:8; Ashel Avraham Butchach Tinyana 16] There is also Kabalistic reasons mentioned behind this. [Arizal ibid]

[5] See Aruch Hashulchan 8:10; Piskeiy Teshuvos 8 footnote 123; The reason for this is in order so the right side remains on the right.

[6] Machatzis Hashekel 8:6; Arizal ibid

[7] As by the Tallis Gadol the inner lining is placed on the inner top side of the Tallis, and hence it should not be facing out. Likewise by the Tallis Katan we are particular for it to have two holes.