This part is a kind of semiconductor called K3995.

Function of this product has Silicon N-channel enhancement MOSFET.

Manufacturers : Panasonic

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Some of the text within the PDF file :

This product complies with the RoHS Directive (EU 2002/95/EC). Power er MOSFETs 2SK3995 Silicon N-channel enhancement MOSFET For high speed switching circuits For PDP  Features  Medium breakdown voltag: VDSS = 200 V, ID = 30 A  Low ON resistance, optimum for PDP panel drive  Package  Code TO-220C-G1  Marking Symbol: K3995  Pin Name 1. Gate 2. Drain 3. Source Drain-source surrender voltage Gate-source surrender voltage Drain current Peak drain current *1 VDSS VGSS ID IDP Drain reverse current IDR Peak drain reverse current *1 IDRP Avalanche energy capability *2 Drain power dissipation Junction temperature Storage temperature EAS PD Tj TC = 25°C Ta = 25°C *3 Tstg  Electrical Characteristics TC = 25°C±3°C Drain-source surrender voltage Drain-sour [ ... ]

K3995 PDF Datasheet Download