bought this adapter to use my old Nikon (Nikkor) glass with a Fujifilm X-T1 that I bought specifically for this purpose. The adapter works perfectly for this purpose. The connection is positive and firm. You may need to move the lens just a little to get positive lock, but that goes for Nikon bodies too! I have used the adapter with F-mount and E-series lenses and it performs all the functions as advertised with the X-mount Fuji body. Yes, the camera must be set to manual mode using the switch on the front of the housing and "use without lens" must be set to "yes" in the menu. It is also possible to use the camera in aperture priority mode with a manual lens. (You choose the aperture setting and the camera chooses an exposure time. It's so much fun to pull out the old glass and shoot manually, just like in my old film days. My old Nikon lens does work manually on my Nikon DSLR, but the violin factor is too big to be worth it. On a Fuji X-T1 or similar body, all the manual controls are right there, making using those old wonderful lenses you paid big bucks easy to use again. This one Adapter seems to be on par with many I've sold at a much higher price Attached is a photo of the X-T1 with the Nikkor 50mm f/1.4 attached!