Iigiya zeyunithi yokuqhuba (i-Helical Gear Set) yothumelo lwe-EV, iigiya ze-Helical ngamazinyo egiya e-cylindrical ahambisa i-torque ukusuka kwishaft ukuya kwenye.Ilula, iyasebenza kwaye ihlangene, ibenza babe lukhetho oludumileyo kwizicelo ezininzi.
Olu hlobo lwegiya lwenzelwe ukumelana ne-torque ephezulu kunye neemfuno zesantya esiphezulu sezicelo zezithuthi zombane kwaye zihlala zenziwe ngezinto eziphambili ezifana nentsimbi yealloy okanye ezinye iintsimbi ezomeleleyo.