Futaba 1st generation and GRI
GRI (George Risk Industries) appear to have only sold a subset of the full Futaba 1st generation product range. GRI were able to provide me with datasheets for both KBM and KBM-LP, although amusingly but unfortunately, they do contain mistakes. KBM is cited as 0.03±0.01″ pretravel and 0.12±0.01″ total travel and a 3.5±0.8 oz operating force. That’s 99 gf in 0.8 mm, which is far from true. Even more amusingly, KBM-LP is cited as 0.045±0.01″ pretravel, going back upwards for a total travel of 0.01±0.02″. While I do appreciate their efforts in providing these details, it would have been nice to have had more accurate data! GRI did not comment on these observations.
KBM is listed as being available in a latching variety, which I at the time of writing may yet be undiscovered in a GRI keyboard. The switch itself is of course documented, being used by Televideo in particular.
The datasheets do not bear any dates.