Quadrant Private Equity has offloaded its majority stake in Quad Lock, a manufacturer of products that let outdoor enthusiasts mount phones on their bikes and boats, to Swedish giant Thule in a deal that values the Melbourne-based company at $500 million.

Stockholm-listed Thule is best known for roof boxes, bike racks, jogger strollers for children and ski and snowboard bags. With the purchase, it adds products that lock smartphones to bikes, boats or cars that can withstand tough terrain to its broader portfolio.