rapa
Ko te rapa he rauemi polymer tino rapa me te whakarereketanga whakahuri.
He rapa i te pāmahana o roto, ka taea te whakaputa i te rerekeetanga nui i raro i te mahi a te kaha iti o waho.Ka taea te hoki ki tona ahua taketake i muri i te tangohanga o te kaha o waho.
He maha nga momo rapa tae atu ki te EPDM, Neoprene Rubber, Viton, Natural Rubber, Nitrile Rubber, Butyl Rubber,Timprene, Synthetic Rubber, etc.