Sizes:

Frame Width: 4 inch (100 mm)

Internal Size: 16 x 20 inch (410 x 510 mm)

Internal Size: 20 x 24 inch (510 x 610 mm)

Internal Size: 24 x 30 inch (610 x 760 mm)

Internal Size: 24 x 48 inch (610 x 1220 mm)