Wadanne sassa ne sashe guda ɗaya tare da zaren waje ya ƙunshi?
Namiji masu zaren sakawa kawai sun ƙunshi ƙaramin bututu mai ƙarfi wanda ake zaren ciki da waje.Suna iya zuwa da wasu fasaloli daban-daban waɗanda galibi suna taimakawa tare da shigarwa:Wasu samfurori suna da kullun a kusa da saman; yana buƙatar ƙarin mataki a cikin tsarin shigarwa.Wasu model suna da cutouts. Gabaɗaya su ne abubuwan da ake sakawa da kai, wanda ke nufin suna buƙatar ƙaramin aiki don shigarwa.Nau'in saka na ƙarshe na namiji yana da maɓallan da aka danna ciki bayan shigarwa don ƙarin tsaro da juriya na cirewa.