Four Quadrant Bar Phantom Rectangular Bar Phantom Physical Dimensions: 22 1/4″ x 17″ Bar Sizes: 2mm,2.5mm,3mm,3.5mm Square Bar Phantom Physical Dimensions: 16 7/8 Square Bar Sizes: 1/8″, 5/32″, 1/4″, 3/16″ Circular Bar Phantom Physical Dimensions: 16″ Round Bar Sizes: 2mm,2.5mm,3mm,3.5mm