I found several boxes of these old German cards of silky cotton thread - probably for darning - in an old haberdashery warehouse I cleared. GEM.SPLITGAREN B.C.H printed on the cards, which are 10.5cm tall. Some of the cards are a little discoloured with age. I have grouped them into lots of 3 complementary colours, or you can get all 12 !
Lots more delightful haberdashery from the same source in my Etsy shop.