Telephone Sevenoaks (01732)522471. Corten Steel Stairs, Corten Stairs, Corten Steel Garden Steps and Corten Steel Step risers by ADEZZ fabricated from 3mm metal thickness 100cm, 125cm, 150cm, 200cm, 250cm and 300cm wide with a choice of 2,3,4,5,6,7,8,9,10,11,12,13,14,15,16 and 17 steps.