This part is a kind of semiconductor called 1N975B.

Function of this product has ZENER DIODES.

Manufacturers : General Semiconductor

Image and pinout :

Some of the text within the PDF file :

NEW PRODUCT NEW PRODUCT NEW PRODUCT 1N957 THRU 1N978 ZENER DIODES FEATURES DO-35 ♦ Silicon Planar Power Zener Diodes ♦ Standard Zener voltage tolerance is ±5% for “B” suffix. Other tolerances are available upon request. max. ∅.079 (2.0) max. .150 (3.8) min. 1.083 (27.5) Cathode Mark min. 1.083 (27.5) max. ∅.020 (0.52) MECHANICAL DATA Case: DO-35 Glass Case Weight: approx. 0.13 g Dimensions are in inches and (millimeters) MAXIMUM RATINGS Ratings at 25°C ambient temperature unless otherwise specified. SYMBOL VALUE UNIT Zener Current (see Table “Characteristics”) Power Dissipation at TL = 75°C Junction Temperature Storage Temperature Range NOTES: Ptot Tj TS 500(1) 175 – 65 to +175 mW °C °C (1) TL is measured 3/8” from body. SYMBOL MIN. TYP. MAX. [ ... ]

1N975B PDF Datasheet Download