The zener diode can stabilize the voltage by allowing the current to vary over a large range.

Specification:
Type: DO-41
Zener voltage: 3.9V
Power Dissipation: 1W
Product Dimensions: 4 x 2.4mm/0.16 x 0.09inch(L*OD)
Total Length：60mm/2.36inch
Main Body Length: 4mm/0.16inch
Packing List: 20 Pcs x Zener Diode Assortment

Advantage:
Zener diodes have good stability, low power loss, and high efficiency.
Zener Diode can be used for product development, experiments, maintenance, production, etc.

Note:
Please pay attention to distinguishing polarity when using it to avoid malfunction or damage.