5x and 5y of the opening 5 by the tubular welts 17 and 25 and is finished about the points 5a and 5b by the triangular fabric panels 21 and 23 which join the tapered marginal edges 17a 25a and 17b 25b respectively of welts 17 and 25 fig1 and 19 illustrate an embodiment wherein the extension of the joining triangular fabrics are reduced with respect to the previous embodiment in fig1 and 19 the article is represented under the same conditions as the article of the previous embodiment is shown in fig1 and 14 in fig1 and 19 the same reference characters are applied to the same elements with the reference characters in fig1 and 19 being increased by 100 the welt 117 corresponding to the welt 17 is formed from two plies 117x and 117y of substantially equal length the ends of the portion 117x are indicated at 117a and 117b and are tapered as the portion 117x is formed with a gradual withdrawal of the needles along the needle front the ends of the portion 117y are indicated by 117a 1 and 117b 1 and are straight instead of being tapered all of the needles being maintained during the forming of the portion 117y portion 117y is knit after portion 117x and portion 117y is knit only on the needles remaining in action after the desired amount of needles have been withdrawn from action to form the tapered edges 117a and 117b accordingly.