Ko te whakamau i te ahunga maha e pa ana ki te hangahanga uaua, kahore he tara, he peka maha iti, he kohao ranei, ka whiwhi ma te whakamahi i te mate whakakotahitanga, kotahi te whakamahana me te whiu kotahi o te perehi.I tua atu, he tino nui te whakaritenga mo te tone o te perehi.I nga wa o mua, na te nui o te tinana whakatikatika diameter nui, ka taea anake te mahi ma te wehewehe i te hiriwa katahi ka whakaemihia ka paiherea.Mena ka whakamahia te whakamaarama mate maha, ehara i te mea ka taea te hanga tika i te ahua i roto i te wera kotahi, engari ka taea hoki te whakakotahi i te rua o roto, ka tino whakapai ake i te kaha me te rerehua o te waatea i te ahunga muka, me te whakaiti i te utu hua. .