This part is a kind of semiconductor called MAC224A10.

Function of this product has TRIACs 40 AMPERES RMS 200 thru 800 VOLTS.

Manufacturers : Motorola

Image and pinout :

Some of the text within the PDF file :

MOTOROLA SEMICONDUCTOR TECHNICAL DATA Order this document by MAC224/D Triacs Silicon Bidirectional 40 Amperes RMS Triode Thyristors . . . designed primarily for full-wave ac control applications such as lighting systems, heater controls, motor controls and power supplies. • Blocking Voltage to 800 Volts • All Diffused and Glass-Passivated Junctions for Parameter Uniformity and Stability • Gate Triggering Guaranteed in Three Modes (MAC224 Series) or Four Modes (MAC224A Series) MAC224 Series MAC224A Series TRIACs 40 AMPERES RMS 200 thru 800 VOLTS MT2 G MT1 CASE 221A-04 (TO-220AB) STYLE 4 MAXIMUM RATINGS (TJ = 25°C unless otherwise noted.) Rating Peak Repetitive Off-State Voltage(1) (TJ = –40 to 125°C, 1/2 Sine Wave 50 to 60 Hz, Gate Open) MAC224-4, MAC224A4 MAC224-6, MAC2 [ ... ]

MAC224A10 PDF Datasheet Download