Check the listing for details. SOT-23 TL431 SMD Adjustable Precision Shunt Regulator 20 Pieces. Condition: New – Open box. Listed at 2.48 USD. TL431 Shunt Regulator in the SOT-23 PackageThe TL431 is a three-terminal adjustable shunt regulator offering excellent temperature stability. This device has a typical dynamic output impedance of 0.2. The device can be used as a replacement for zener diodes in many applications. This item is sold as a lot of 20 pieces. Please Note: Items delivered using complimentary standard shipping are sent as a first class letter and will only include limited tracking data. If you would like or require full tracking information, please upgrade to the First Class Package option. Please also be aware that this item cannot be shipped to certain US protectorates, to international destinations, or to freight forwarders at this time. Orders to freight forwarders will be cancelled!