Sometimes concerns are raised regarding the terminals’ polarity identification for the magnetic buzzer AST7525MATRQ from Mallory Sonalert Products Inc.
The corner that does not have the metallic tab sticking out can be used to determine which terminal is positive (+) and which is negative (-). The positive pin is always the first pin from the cutoff corner pin when looking in counterclockwise direction from the top view. For example, if we look at the image below, the “+” pin is the top left pin and the “-" pin is the lower left pin.
DigiKey Part Numbers based on packaging type for this part:
458-AST7525MATRQCT-ND
458-AST7525MATRQTR-ND
458-AST7525MATRQDKR-ND