Purling stitches together through the back loops, as in p2tog-b, p3tog-b, etc. is a twisted left leaning decrease. A twisted purl decrease is the mirror of the straight purl decrease (p2tog, p3tog, etc.)
Purl 2 Stitches Together Through the Back Loops
Abbreviation: p2tog-b
With yarn in front and right needle behind left needle, twist right needle so it can go into 2 stitches together from left to right. Bring right needle to usual purl position and p2tog.
Purl 3 Stitches Together Through the Back Loops
Abbreviation: p3tog-b
With yarn in front and right needle behind left needle, twist right needle so it can go into 3 stitches together from left to right. Bring right needle to usual purl position and p3tog.
Purl 4 Stitches Together Through the Back Loops
Abbreviation: p4tog-b
With yarn in front and right needle behind left needle, twist right needle so it can go into 4 stitches together from left to right. Bring right needle to usual purl position and p4tog.
Purl 5 Stitches Together Through the Back Loops
Abbreviation: p5tog-b
With yarn in front and right needle behind left needle, twist right needle so it can go into 5 stitches together from left to right. Bring right needle to usual purl position and p5tog.
See also: Knitting Stitches Together, Purling Stitches Together, Knitting Stitches Together Through the Back Loops,
