Mamiya 300mm f/2.8 APO Telephoto Manual Focus Lens for 645

The 300mm f/2.8 APO is an astounding achievement in medium format optics, using Mamiya's ultra-low dispersion glass and computer aided design to produce the world's only medium format 300mm f/2.8 lens. It exhibits complete correction of chromatic aberration, for optimal performance even wide open. It is designed for use with the 2X Tele-Extender for use as a 600mm f/5.6 lens. The 300 APO also features a rotating tripod mount, collapsible lens hood and hood extension, and a drop-in filter set.

Applications include available light photography for reportage, wildlife, sports, fashion and beauty.
Specifications
Construction 8 Groups/ 9 Elements
Angle of view 13°
F stop range f/2.8-22
Closest Focusing Distance 11' 5.9" / 350cm
Maximum Magnification 1:1
Filter Size Drop-in (6 types)
Dimensions (Length x Diameter) 5.5 x 9.3" / 139.5 x 237mm
Weight 5 lbs. 15 oz. / 2,700 g.