A hinge for supporting a sash between a closed position, in which it lies within a fixed frame, and a plurality of open positions, in which it extends at an angle to the fixed frame. The angles of the plurality of open positions being determined by a restricting means between a support track (2) and a slider (11) mounted thereon. A support block (1 ) provides increased bearing surface and support for the fixing means (5) between the support track (2) and a link (3). A stay open restrictor device for preventing closure of a sash into a fixed frame.