The Japanese version of the caltrop is called "makibishi". Makibishi were sharp spiked objects that were used in feudal Japan to slow pursuers and also were used in the defence of samurai fortifications. Iron makibishi were called "tetsubishi", while the makibishi made from the dried seed pod of the water caltrop, or water chestnut (genus "Trapa"), formed a natural type of makibashi called "tennenbishi". Both types of makibishi could penetrate the thin soles of shoes, such as the waraji sandals, which were commonly worn in feudal Japan.