The Leopold FC660C keyboard only.
The original design.
Some early units included a set of two loose 7mm hex-shaped breakout PCB standoffs that were designed to be screwed into the rear cover plate using M3 x 5mm countersink screws. Later units had the standoffs permanently riveted into the rear cover plate.
Features two small but decisive improvements over the Mark I: new logo badges (fabricated using the same process as on luxury cameras) and pockets on the bottom face that match our ultra-grippy non-marring v2 bumpons.
Note, however, that the bumpons for the Mark II came in a special shimmed form (with a thin clear plastic layer backing them) since the pockets are slightly deeper on the H6 MK2 to be able to use the standard bumpon thickness.
There may in some cases be an alignment issue on the Mark II titanium units, causing the breakout PCB to sit a bit short of its port in the housing. This can be fixed with a spacer of the following specs:
Fixed in place with two M3 x 6mm button-head screws through the breakout PCB.
If you purchased one of these and are experiencing plate misalignment due to a short set of rear cover plate standoffs, just email client service to obtain a set of spacers.
Just over four pounds in aluminum, and over 7 pounds in steel (with the keyboard installed).