Ko ngā peera pōro whakapā koki rarangi rua e rite ana ki ngā peera pōro whakapā koki rarangi kotahi e rua kua whakaritea whakamuri, engari he iti ake te wāhi tuaka e nohoia ana. Ka taea e rātou te whakauru i ngā kawenga radial me ngā kawenga tuaka e mahi ana i ngā taha e rua. Ka whakaratohia e rātou he whakaritenga peera pakari, ā, ka taea te whakauru i ngā wā piko. Kei te wātea ngā peera i roto i te hoahoa tuwhera taketake me te hoahoa hiri.
