Police have been out and about today asking motorists to stop and read the registration plate of a vehicle parked 20.5 metres away - the legal standard set by the DVLA.
They are warning that drivers who fail this roadside eyesight test could have their licence revoked instantly.
Many sailed through the spot-check - but for others it was a wake-up call, as our correspondent Carl Edwards reports.
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A wet and windy night to come, with rain turning heavier overnight. Feeling particularly blustery in coastal areas.
In today's Newsweek Wales, Carl talks to Dr David Bailey from The BMA about how to ease the pressure on the Welsh NHS.
Plans to open a branch of Sainsbury's in a new development in a Pembrokeshire town have been criticised by local businesses.