I opened the synthetic-thread drawer and selected upholstery thread in a small zipper bag that also contained a bobbin for the treadle machine, a needle stuck into a snippet of red wool, and a large coil-less safety pin.
?? I must have had a reason for putting a pin in with the thread; I put it back in when I was done.
The needle chosen for the upholstery thread was too coarse for the job at hand. (Adding snaps to a walker bag made of tissue-weight mock leather lined with thin synthetic knit.)
So I added a #8 "sharp" needle to the kit -- and then ADDED A NOTE SAYING THAT IT IS A #8 NEEDLE.
There are gages that tell you what size knitting needles are; I wonder whether there is a way to sort out sewing needles that have gotten scrambled. The trick of putting a needle and a needle of known size on a flat surface, then looking to see which way a needle laid over them slants, works well for knitting needles, but my fingers are too big to do that with sewing needles.