Alps KFNM

KFNM is an Alps membrane keyboard type. This is known from the Toshiba T1000XE, where the specific model is KFNMBA002B. The return force and tactile feel is provided by an inverted rubber sleeve, and membrane actuation uses a small spring contained within the keycap.

Pawel from Old Crap Vintage Computing provided some photographs of the keyboard mechanism from the T1000XE: