Nooky-Hesum For Leica Screw Mount cameras.  The Nooky-Hesum was a variation of the original Nooky (1935).  This device allowed close focusing from 1:17.5 to 1:6.5.  This device is a combination of an extension tube and a small correction window that fits over the rangefinder window allowing proper focus.  The earlier Nooky was first available in Nickel finish.  The model shown above is finished in chrome and black paint. It could be used on the Summitar, Summar or Hektor 50mm lenses.  It came in two models.  The first omitted the Summitar (had not been put into production yet).  The second added the Summitar to the front engravings.  This was done in 1939.  A fun tool if you plan on taking your Leica into the realm of close-focus - a place where the rangefinder style camera is least suited (one of my reasons to invest in a Leicaflex outfit with proper Macro focus lens).