For vehicles that spend more time in town or on a variety of different roads, a rev limiter could be a shrewder choice.

Leggat said: “We set the rev limit at the point of maximum torque, so there is no performance loss.

"However, the driver cannot work the engine beyond this into a wasteful rev range. Most drivers quickly learn to drive accordingly and change up through the gears earlier.

"This has advantages for fuel economy, but also for vehicle longevity, reliability and better driving standards.”

Wiggins agreed: “Limiting maximum speed has had no negative impact on our drivers and is now a firm part of our fleet policy.

This also includes a pre-driving assessment for new drivers, driver risk assessment, vehicle safety specifications being a mandatory part of contract specifications and Royal Mail’s Zero Accident Programme.”

The cost savings offered by rev limiters are clear, and not just for large fleets such as the Royal Mail’s.

Every van operator can benefit from using one of these devices, with fuel savings of 25% easily achievable for a small initial outlay, and it also has the added advantage of helping to protect the driver’s licence.