Palm thimble in metal, used for sewing sashiko stitching for example. By supporting the eye of a long needle against your palm and holding the needle between your thumb and middle finger, you can sew long stretches of running stitches faster. This sewing technique is called unshin and is used for ordinary hand sewing as well as sashiko stitching in Japan.
Once you have learned the technique, it is a very practical way to sew by hand.
This thimble (or palm thimble as it is called in English) is made of metal and is open at the back so you can adjust the size by squeezing or pulling the ring apart.
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