These classic Scalextric brass terminal pins have a barrel diameter
of 1.95mm and were used throughout the 1960s, 1970s, and 1980s.
They are used to secure the wires from the Scalextric motor to
the pick up braids on the guide assembly, see the guide pictured
above.
This classic Scalextric guide blade is sometimes referred to
as G21, G22 or G23. They are also used as replacement pins where
wires are connected to the headlamp and tail lamp bulbs,
for example, in the Scalextric Ford Escort XR3i or the various
Police Rover 3500 vehicles.
They are also used on the Scalextric RX
motor to make contact with the motor brush.