Mamiya RB67 No.1 Extension Tube  type_Projectors This Kenko DG extension tube

This Kenko DG extension tube set includes 10mm and 16mm tubes which can be used together or separately to provide substantial close-up capability with most Micro Four Thirds lenses (sold separately)

No light metering on this one

This is a good quality Nikon Y48 yellow filter in the original

The Manfrotto 029 is an old-school

we've put together a simple kit that has everything you need to get started

Mamiya RB67 No.1 Extension Tube &nbsptype_Projectors This Kenko DG extension tubeIf your RB67's bellows extension isn't taking you quite as close as you'd like to go, this 45mm extension tube will provide a fair bit of extra magnification. Good working order, minor cosmetic wear.