Consumers buying electrical goods on the internet in the run-up to Christmas are being warned that many of them can cause serious injuries.
An industry safety body says as many as one in ten items bought online can result in a fire.
Shoppers are being advised to take particular care when buying goods from outside the European Union, as they are often not designed to be used in Europe.
"Faulty electrical products can cause electric shock, " says Kevin Sweeney, who works for a testing laboratory.
"And of course, electric shock can kill people."
At the Intertek labs in Leatherhead in Surrey there is a collection of "horrors" to underline his point.
One is the charred remains of a sandwich-maker.
On the bottom it is marked with the name of a reputable brand, and it even has the CE safety mark.
But it turns out it contained no thermal fuse, so when it was left on it just got hotter and hotter, until it burst into flames.
The markings on the bottom were just a forgery.