urine dipsticks (often made of metal or plastic)
https://gyazo.com/34b9228beab380e0533d92f0051bd53c
party science p.181
It was the first book written on the technique that later became known as the "KJ method.
It was Tadao Umesao who suggested the name "KJ method" in KJ method Let the chaos speak for itself, p.212, arguing that the name "Paper Kire Method" should be changed.
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