This part is a kind of semiconductor called D1207.

Function of this product has METAL GATE RF SILICON FET.

Manufacturers : Seme LAB

Image and pinout :

Some of the text within the PDF file :

TetraFET D1204UK METAL GATE RF SILICON FET MECHANICAL DATA C D (2 pls) E B 1 2 3 A G GOLD METALLISED MULTI-PURPOSE SILICON DMOS RF FET 30W – 12.5V – 500MHz SINGLE ENDED FEATURES • SIMPLIFIED AMPLIFIER DESIGN • SUITABLE FOR BROAD BAND APPLICATIONS • LOW Crss 5 4 H I F M K J N DT PIN 1 PIN 3 PIN 5 SOURCE (COMMON) PIN 2 SOURCE (COMMON) PIN 4 DRAIN DIM A B C D E F G H I J K M N mm 6.35 DIA 3.17 DIA 18.41 5.46 5.21 7.62 21.59 3.94 12.70 0.13 24.76 2.59 4.06 Tol. 0.13 0.13 0.25 0.13 0.13 MAX 0.38 0.13 0.13 0.03 0.13 0.13 0.25 Inches 0.250 DIA 0.125 DIA 0.725 0.215 0.205 0.300 0.850 0.155 0.500 0.005 0.975 0.102 0.160 Tol. 0.005 0.005 0.010 0.005 0.005 MAX 0.015 0.005 0.005 0.001 0.005 0.005 0.010 GATE SOURCE (COMMON) • USEFUL PO AT 1GHz • LOW NOISE • HIGH GAIN [ ... ]

D1207 PDF Datasheet Download