The 47-year-old driver had pulled into the layby near Weston Rhyn, Oswestry for a break at around 8.30am on Friday.
While outside his white Ford Transit van, he was confronted by two men travelling in an old style black BMW car.
One of them pushed him against the side of his van, threatened him with a knife and ordered him to open his vehicle.
On seeing the van was empty, the driver was pushed again suffering a small cut to his face as his two assailants drove off towards Oswestry.
Police Constable Lisa Bullock, the investigating officer, said the incident was being treated as an attempted robbery. She appealed for witnesses to contact Oswestry police station by calling 101.
“The victim’s van had a sign with the word ‘Polyroof’ written on it. Do please contact the police if you spotted the van in the layby or have any information relating to this incident.”
One of the offenders was white, about 5ft 8ins tall, in his late twenties, of slim build with long, jet black medium length hair and had two golden studs in his left ear.
He was wearing white trainers, faded blue denim jeans and a dark blue tracksuit style top.
The second man was also white, in his late twenties, about 6ft tall with short cropped brown hair and wearing dark blue jeans and a dark coloured top.
Information can also be given to the anonymous Crimestoppers charity by calling 0800 555 111.
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