Indandatho ihlukana ngephuzu elilodwa futhi yagoba yaba yisimo se-helical.Lokhu kubangela ukuthi iwasha isebenzise amandla entwasahlobo phakathi kwekhanda le-fastener kanye ne-substrate, egcina iwasha iqinile ngokumelene ne-substrate kanye nentambo yebhawudi iqine ngokumelene nenathi noma intambo ye-substrate, okudala ukungqubuzana okwengeziwe nokumelana nokujikeleza.Amazinga asebenzayo yi-ASME B18.21.1, DIN 127 B, kanye ne-United States Military Standard NASM 35338 (ngaphambilini eyayiyi-MS 35338 kanye ne-AN-935).