A chain of central Auckland convenience stores sold unsafe travel plug adaptors despite repeated warnings.
Dtown and Zolo Limited, trading as City Star Convenience Stores and Britomart Magazine, were fined a total of $80,000 at the Auckland District Court on Tuesday.
The companies had been unable to say how many adaptors they had sold through their chain of 15 stores.
Worksafe New Zealand said the adaptors didn't have adequate protection to prevent contact with live parts, leading to a risk of fire and electrocution.
"The adaptors are of particular concern given that plugs are used at skirting board level and easily accessible by infants and young children," said Energy Safety Compliance Officer Richard Lamb.