He ara rere o roto, o waho hoki ngā porowhita o ngā peera pōro whakapā koki e nekehia ana tetahi ki tetahi i te ahunga o te tuaka peera. Nō reira, he pai ngā peera mō ngā kawenga radial me te tuaka e mahi tahi ana. Ka piki ake te kaha kawe kawenga tuaka o ngā peera pōro whakapā koki i te pikinga o te koki whakapā.
