The Garforth-based business was founded by John and Madge Skewes in 1965, producing Hornby-branded instruments.
Having grown from a home-based business to occupying 67,000 sq ft of premises, the firm now employs 70 people and produces 4,500 products, which are sold in the UK and Ireland and exported to 85 overseas markets.
The business has seen extensive growth since 1990. In the 12 months to March 31 2014, JHS saw revenue growth of six per cent, with exports rising from 15 per cent of sales to 20 per cent.
Chairman and founder John Skewes said: “I give my thanks to many people - supportive customers, reliable suppliers, loyal staff and a caring encouraging family - who have all played their part.”