Alto Partners, an Italian mid-market buy-out firm, has realised a 48% annualised return before fees after selling its stake in automatic door maker BFT to France's Somfy International for €94m ($114m).

BFT is number four, in terms of turnover, in its market in Europe, with sales of €58m. Somfy International has sales totalling €517m in 40 countries. BFT's management said the deal will give it global access.