The Truth window hinge 30744 and 31133C – Replacement is the Wi1475, which is the most common window hinge used with Truth Operators.   We find the number 31133C stamped on the window track, and the number 30744 stamped on the arm that goes from the window track to the arm attached to the window.  We sell this window hinge in pairs, meaning top and bottom.  If your window is the opposite hand, then the bottom hinge goes to the top, and the top hinge goes to the bottom.

on hhis hinge is stamped 30744 and 31133c.