This part is a kind of semiconductor called 2N3957.

Function of this product has N-Channel Dual Silicon Junction Field-Effect Transistor.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

B-6 01/99 2N3957, 2N3958 N-Channel Dual Silicon Junction Field-Effect Transistor ¥ Low and Medium Frequency Differential Amplifiers ¥ High Input Impedance Amplifiers Absolute maximum ratings at TA = 25¡C Reverse Gate Source & Reverse Gate Drain Voltage Gate Current Total Device Power Dissipation (each side) @ 85°C Case Temperature (both sides) Power Derating (both sides) – 50 V 50 mA 250 mW 500 mW 4.3 mW/°C At 25°C free air temperature: Static Electrical Characteristics Gate Source Breakdown Voltage Gate Reverse Current Gate Operating Current Gate Source Voltage Gate Source Cutoff Voltage Gate Source Forward Voltage Drain Saturation Current (Pulsed) Dynamic Electrical Characteristics Common Source Forward Transconductance Common Source Output Conductance Common Source Input Ca [ ... ]

2N3957 PDF Datasheet Download