These fixtures consists of black buttons with concave surface and rounded frame (by their sister company, Dewhurst).
1930s to 1940s
In the 1930s, the black buttons were slightly redesigned to look protrude less, and the hall stations have a very old style to them
1950s to 1960s
These fixtures consists of black buttons which were smaller. Some elevators also had the old style 1920s-1960s Dewhurst buttons.
1970s to mid 1980s
Dewhurst US81 Compact
Marryat & Scott stopped using their own black buttons and switched to using Dewhurst US81 Compact buttons in the early 1970s.
- Main article: List of Kone elevator fixtures#M-Series
After been bought by Kone in 1979 and changed name into Kone Marryat Scott, fewer late models of Kone Marryat Scott elevators in the early to mid 1980s used Kone M-Series fixtures.