Iron base, XRF set of 17 discs (7 mm), see BS-184A-7MM, BS-185A-7MM, BS-17-4PHA-7MM, BS-192-7MM, BS-253-7MM, BS-179C-7MM, BS-303-7MM, BS-81P-7MM, BS-82D-7MM, BS-83G-7MM, BS-316C-7MM, BS-317L-7MM, BS-2205-7MM, BS-85D-7MM, BS-86F-7MM, BS-347A-7MM, BS-355-7MM