Launched in 1992 by three engineers fed up of fitting awkward air-conditioning equipment, this business makes easy-to-install condensate removal pumps. The East Sussex company has made seven acquisitions since 2015, including in France, Germany and Australia. Under chief executive Adrian Thompson, 52, profits grew to £11.7m in 2018, which excludes £8.5m of acquisition costs. In December, it was acquired for an undisclosed sum by Inflexion, the private equity firm. During the pandemic it has donated to its local food bank.