Ko te RN he taapiri e rua nga waahanga. Whai muri i te taapiri i tetahi waahanga o te RN ki te whakapiri, me tono te whakapiri-waahanga-rua-rite ki te whakamahi i roto i te waa (te ora o te kohua) e whakatauhia ana ehara i te mea ko te kiko o te rapa anake, engari na etahi atu kai o te hanga (hei tauira, kapia, antioxidants, whakarewa, me etahi atu). Ki te kore e whakamahia te whakapiri i roto i tenei waa, ka kaha ake te uaua ki te tono, ka tere te piki o tona pokey tae noa ki te wa e kore e taea te huri. No reira, kua kore e whakamahia.
Tūtohu inenga:
Mo te rongoa i te whakapiri o te 100 nga wahanga i te taumaha (pbw) i runga i:
| rapa Graft-Chloroprene(te ihirangi rapa āhua 16%) | 3-5% pbw RN |
| rapa Chloroprene(te ihirangi rapa āhua 20%) | 5-7% pbw RN |
| Hydroxyl polyurethane(te ihirangi polyurethane āhua 15%) | 3-5% pbw RN |
