Zogulitsa
Mipira ya 4-point-contact ili ndi mphete yamkati yomwe imagawanika kukhala zidutswa ziwiri.Imodzi yokha mwa mayendedwe awa imatha kunyamula katundu wa axial mbali zonse ziwiri.mphete yakunja yokhala ndi mpira ndi khola ikhoza kukhazikitsidwa mosiyana ndi magawo awiri amkati a mphete.Mbali yolumikizana ndi 35 ° imalola kuti axial alemedwe kwambiri.Mtundu uwu ndi woyenera kunyamula katundu woyera wa axial kapena katundu wophatikizana kumene katundu wa axial ndi wapamwamba.Zimbalangondozi zimakhala ndi mazenera amkuwa opangidwa ndi makina.