A Christchurch factory is shifting its operations to Australia and Vietnam with the loss of about 50 jobs.
Schneider Electric - which produces light switches and power plugs - was formerly part of Christchurch company PDL, with a decades-long history in the city.
Union E tū coordinator Phil Knight said the products Schneider made were in most New Zealand homes and instantly recognisable to most people.
He said the announcement comes just weeks after ABCorp announced it was closing its Christchurch plastic card factory and relocating abroad.
Mr Knight said there have been a string of closures, and every time it's a blow for union members and the economy.
Schneider said in a statement it listened to staff as part of a month-long consultation period.
The firm said it would work with staff to find other parts of the company they might be interested in working in but did not say if these jobs would be based in New Zealand.