It’s the sign that means ‘national speed limit applies’, but – that in itself – that means more than one thing.
The national speed limit is different on different types of roads, with a speed limit of 60mph applying on a single carriageway, and 70mph on a dual carriageway.
In truth, the national speed limit is 30mph unless signs – such as this one – state otherwise.
In Wales, that’s now 20mph. And what’s more, the type of vehicle you have changes things, too.
For example, on single carriageway, roads vehicles towing trailers are limited to 50mph by that sign, as well as those tugging caravans.
Buses, coaches and minibuses must also only do 50mph on single lane roads.
Basically, there are a lot of rules to remember, but if you’re in a car that isn’t pulling something it’s a bit simpler.
In a Facebook group called ‘Idiot UK Drivers Exposed’ the sign was posted, asking people to state what they think it means.
Most people seemed to get it right, but others saw the opportunity for a bit of a joke.