This sale is for a genuine Mamiya 645AF Extension Ring No. 1 (NA401) to fit all of the Mamiya 645AF / Phase One auto focus cameras. It is in near mint condition.
This extension ring is in perfect mechanical and electronic condition, and you can download a copy of the Mamiya instructions from this website. Apart from that there is not a lot to say – everything works perfectly. There are normal minor usage marks on the ring but no damage at all. Please note that no end caps are supplied with this extension ring.
This extension tube will give you 0.15 to 0.30x magnification with a standard 80mm lens.
I tend to use these rings just to get a closer focus with my 150mm and 210mm lenses – it is so small that it is no problem to carry around in case you need it.