Low-profile

Low-profile (adj.) — a switch module with a shorter height than previous switches.

For example, Cherry M9 was described by Cherry as "low-profile" because it was significantly shorter than the standard M7 switch. By modern standards, M7 is oversized, and M9 and MX are standard profile, yet the Cherry M6 switch was also described as "low profile" in Cherry's 1973 and 1974 Switches & Keyboards catalogues. By 1982, the M6/M7 design had been re-designated "Standard Mounting Height" following the introduction of the smaller M8 and M9 switches.

Cherry ML is Cherry's current low-profile switch, in a form factor that was described originally as "Super Low Profile".

1980s low-profile switches do typically still have the same 3.5–4 mm travel as their larger equivalents, unlike modern low-travel/short-throw switches, which are typically around 2–3 mm.

ITW described the second generation of ITW magnetic valve switches as "low profile" in their patent, even though these are tall switches.

Definitions

The Hi-Tek Corporation patent for the Hi-Tek Series 725 switch—which Hi-Tek themselves describe simply as "Low profile keyswitch"—defines "low profile keyswitch" as follows:

Keyboard specifications for electronic equipment for sale in many industrialized countries require the keyswitch housing to project not more than 17 mm from the attached printed circuit board. A keyswitch which meets the foregoing specification generally is designated as a "low profile keyswitch".

This 17 mm definition is just slightly below the total height of a Cherry M7 switch, being between 19 and 21 mm approximately depending on variant.