The helical circular spiral stair with a metal structure with a thickness of 10 mm, ø internal 140 mm, lamellar beech treads with a thickness of 40 mm. Raling mod. RAIL in varnished metal with double plat uprights of 40x10 mm, 5 horizontal parallel tubes of ø 10 mm, circular metal handrail of ø 33 mm. Triangular landing.