The pump section consists of a piston pump. The piston and cylinder are made of
hardened steel and are carefully lapped together.
The pumps require the addition of a pressure sensor and control equipment in order
to start and stop automatically. The control equipment stops the motor when a preset
pressure has been built up and restarts it when the pressure falls. For this reason
the control equipment is necessary for use with grease-guns. The cut-off pressure is
set by means of the pressure sensor. The control equipment also includes an
automatic circuit breaker to protect the motor. If it trips it can be reset by pressing the