Umda phakathi kocango lomlilo kunye nefreyimu yomnyango awuyi kuba ngaphantsi kwe-10mm, kwaye umsantsa phakathi kocango kunye nefreyimu yomnyango awuyi kuba mkhulu kune-4mm. Emva kokuba umnyango womlilo ufakwe kwaye uvaliwe, i-gap ayifanele ibe nkulu kakhulu, ngaphandle koko ukusebenza kokutywinwa komnyango womlilo kunzima ukuqinisekiswa, kwaye kunzima ukubonakalisa umsebenzi wayo wokunciphisa ukusasazeka komlilo kunye nomsi phantsi kweemeko zomlilo.