Our range of heavy duty friction stay hinges offer superior carrying capacity/load weight for your UPVC windows. Easily fitted to the frames/windows, the heavy duty stays are designed for larger/heavier window sets than your typical UPVC windows There are two key measurements to consider when looking for replacement friction hinges – the stack height and the length. For details of how to measure your current friction hinge, please our Friction Hinge Measuring Guide by clicking here.