Clamp on adaptor ring for the FM600 Matte Box.
Clamp on adaptors are available in sizes: 75mm, 80mm, 85mm, 86mm and 93mm
A complete range of machine crafted interchangeable aluminium adaptors are available and designed to fit directly to the end of the lens barrel, enabling easy attachment of the FM600. For more information, please see this
Matte Box data sheet PDF