Up to 38 jobs could go at a Plymouth-based manufacturing company.
Fine Tubes, which employs about 380 people, produces metal tubing for projects including the Large Hadron Collider in Switzerland.
It blamed a sudden fall in sales due to the economic downturn and the postponement of major projects in some market sectors.
Sales director Brian Mercer said it was committed to its employees but it was "a case of needs must".
He said: "People are still building power stations, but some major clients are putting back projects 12 or 18 months which leaves us with a hole that is difficult to fill.
"Our ability to fill short-term gaps is more compromised by the fact that we do not have the lower-price business any more."
A 30-day consultation period has started with employees.
Mr Mercer said: "It is a situation we take very seriously. We are very committed to our employees. It is a case of 'needs must'."
Dave Springbett, from the Unite union in Plymouth, said: "It's bad news to lose any manufacturing jobs in Plymouth.
"There have already been a lot of jobs lost and there is the possibility of more going in the public sector.
"We need every job we can get."