Yenziwe ngekhwalithi ephezulu ye-polyurethane impahla, amandla aphezulu, iqinile futhi ihlala isikhathi eside.Ukuthuthukiswa okusha kokuvikela uthuli nokuguga, impilo ende kanye nokumelana nokushisa okuphezulu, okwenziwe nge-polyurethane, ukumelana nokugqoka, amandla aqinile, ukumelana nezinyembezi, amandla aphezulu kanye nokumelana nokucindezelwa Ukuzinza kwemoto.