Ko te anga matua o te caster he mea hanga ki te maitai, a ko te matua wira he mea hanga ki te polypropylene (PP) me te kaha o te kawe.
Kei te whakamahia te TPR hei rauemi mata wira, he pai te aukati hinu, te aukati wai, te aukati tarukino me te aukati pokepokea, me te pai o te wiri me te whakaheke haruru.
Ko te waho o te wira he mea hanga ki te rauemi ABS, he anti-corrosion me te kakahu-aukati.Ko te huinga o te kōpae pōro huri noa me nga pōro he nui te kawenga me te kaha ki te kawe.