Ru?t g?i: ???c làm t? Cao su non t? tr?ng cao. ?? b?n t? 5-7 n?m, v?i ?? ?àn h?i ch?m nâng ?? c?t s?ng ???c c?i ti?n t? th? h? ??u, th? h? th? two thi?t k? chu?n cho c? three t? th? n?m: n?m ng?a, n?m nghiêng hay n?m s?p. H? tr? ch?ng h?m, xoa d?u h?m & nu&oci