Ergonomic dhizaini, 360-degree tsigiro, inogadziriswa tightness, kubvisa cervical pressure, yakasununguka kupfeka.
Iyo yakasarudzwa inofema jira yakapfava uye yakasununguka pasina kukurudzira, ine yakanaka ductility, kudziya uye kufema.Uye iyo yakasimba inogadziriswa, uye ndiro yepurasitiki inogona kutsigirwa kaviri.