Nikon F accessory mounting shoe darkroom This helicoid extension tube lets

This helicoid extension tube lets you seamlessly adjust magnification for close-up work with your Pentax 67 and nearly any Pentax 67 lens (not included)

with a particularly thick bottom pad and a semi-rigid internal structure

The #1 lensboard is extended by just short of 1cm for extra versatility on the short rail

A versatile 3-light Fresnel kit with one each of 150W

Nikon F accessory mounting shoe darkroom This helicoid extension tube letsIt's a Nikon F accessory shoe, meant to hold a flash or similar small accessory with compatible mount. This is a cold shoe, so if you're using it for flash work you'll need a separate cable (not included) to connect the flash to the camera.