Picture above is a double spag system. Note that there is four pins or four bolts as apposed to the normal two. This means that the gearbox is reversible. Both pins move in opposite directions and grabs the keeper from both sides. From a security point of view this is extremely durable and strong. So if somebody does put in a jimmy bar and try to prise open the window the locks will not cave. Generally the frame will break before the locks actually break. It is fitted into a 70mm linear frame supplied by linear in the UK and manufactured by Westmeath Windows.
Westmeath Windows and Doors