Wrist mounted light meter, designed using solidworks. Some processing includes sanding. Makes checking light much more lower profile and doesn’t intrude on the design aesthetic of the beautiful Leica M3. I'm not a watch expert so I'm not sure what they call the metal retractable poles are to mount the strap to the watch itself, but the strap I used was recycled from a Casio EAW-DBC-32-1AV, the poles measures 26mm. (Fits 22mm strap)
Don't be alarmed if the meter fits a little loose, I designed it that way because from my prototype without any play, the mount would develop cracks near the mount. I've used this current design for over 3 months now with no issue.
This model was designed to be printed with ABS plastic, you may need to scale down (-0.5%?) if you are printing with other materials.
Since it is going to be in contact with the skin, you should sand it.
Inspired by Detective Conan.