Door system manufacturers Wagon saw pre-tax profits triple from £7.4m last year to £21.7m for the year to March, on the back of turnover increasing from £375m to £409m. Supplying the leading car makers in the world, including Renault, Volkswagen and Ford, Wagon said that integration of the business it acquired in both France and Italy had gone well, allowing its transition from a purely UK to an international engineering company to take place smoothly.