What is a 2/1/2 Cable?

Hi. I just started cabling. I think I’ve finally gotten the hang of basic 2/2 or 1/1 cables. I’m working on an afghan, though, that calls for a 2/1/2 RPC cable. What does that one in the middle mean? Thanks in advance. Happy knitting!

I’m surprised the pattern doesn’t give you directions.

Is it a place where two cables cross each other? If so, it’s probably the one where you slip three stitches to a cable needle and hold in back, knit two from left needle, slide the center stitch (left-most on cable needle) back onto the left needle, knit/purl that stitch depending on the background, and then knit the two stitches from the cable needle.

It is where two cables cross. Your instructions seem to have worked. Thanks so much!!