40m 4-ply fine sashiko threads on handy little cards in a range of contemporary colours, ダルマ 'Daruma' by Yokota is the first sashiko thread I ever bought. This mercerised thread is also great for quilting big stitch and tying quilts (and lace crochet - that's what I bought it for, way back in 1991, without knowing what it was!). Also available, in a slightly different range of classic colours, as 170m skeins.