Mphete inagawanika pamalo amodzi ndikupindika mu mawonekedwe a helical.Izi zimapangitsa kuti makina ochapira agwiritse ntchito mphamvu ya masika pakati pa mutu wa fastener ndi gawo lapansi, zomwe zimasunga makina ochapira molimba pa gawo lapansi ndi ulusi wa bawuti molimbana ndi nati kapena ulusi wa gawo lapansi, kupangitsa kukangana kwambiri ndi kukana kuzungulira.Miyezo yogwiritsiridwa ntchito ndi ASME B18.21.1, DIN 127 B, ndi Military Standard ya United States NASM 35338 (yomwe kale inali MS 35338 ndi AN-935).