Caerphilly-based ventilation system manufacturer Nuaire has been sold for £145 million.
The company, which employs around 450 people, has been sold by Electra Private Equity to the Polypipe group.
Nuaire makes equipment for commercial and residential applications, with its products helping clients reduce their energy consumption and carbon emissions.
From its base on Caerphilly town’s Western Industrial Estate, the business serves more than 5,000 customers in the UK and internationally. In the UK, the company’s customers are mostly contractors and building consultants.
Electra originally invested £23m in the management buyout of Nuaire in 2007.
Mark Huxtable, Chief Executive of Nuaire, said: “We are delighted to be joining Polypipe. The companies share many characteristics, including a similar culture and philosophy, and together we will be better placed to tap into the excellent prospects for the sector.”