EquiVest, the German buy-out firm, has bought STN Atlas Marine Electronics from Rheinmetall for around €100m ($115m) as the German group continues to reduce to its core business of automotives and defence.

EquiVest bought STN, which makes bespoke electronic systems used in ships, particularly in navigation, energy and drives, using cash from its €150m fund and debt supplied by HSH Nordbank, a small German bank.