ngā pito rawhi takirere tirotiro ngutu parera Rahi: DN50 – DN1800 Hononga: pito rawhi cĀhuatanga Hua: He āhuatanga rere kei tēnei takirere ngutu parera. Whakatuwheratia, katia aunoatia kia rite ki te rerekētanga o te pēhanga wai, ā, kāore he haruru, kāore hoki e hiahiatia he mahi a te tangata, he tiaki rānei. Ka iti te pēhanga rere mai, ā, ka whakahaerea noatia te rere e te pēhanga wai. He pai te hiri mō te kore e hoki whakamuri, ā, kāore he turuturu hei karo i te rere whakamuri. He pai ake te pānga me te pēhanga nui ake. Ārai i te waikura, te koroheketanga me te ratonga mahi roa. He whānui te whānuitanga me te diameter ingoa o te DN50 – DN1800.