Flashings and closures are made for particular applications and locations on the roof, with variations to suit the specific profile being used. Supa-Roof sells a range of standard flashings which are aesthetically pleasing as well as made to fit  role which necessitates that they are designed for the structure in question.

Valley Flashing Dimensions 330 x 330
valley-flashing Angle Calculation: 180° Roof Pitch (1.5 x Roof pitch)
Girth 660
Use with Stiffener bend at 158° angle