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Features:

A power delay function - delay 3 seconds after power on.
Output DC offset protection - start protection while output of the DC voltage is above 0.7V
Power off protection - cut off the connection to protect your headphones after power off.
Applied HiFi graded component

Includes:

MINI UPC1237 Headphone Protector Protection Kit x1

Note: It is a kit. You need to solder and build it yourself.