This part is a kind of semiconductor called B4S.

Function of this product has TECHNICAL SPECIFICATIONS OF SINGLE-PHASE MINI SURFACE MOUNT BRIDGE RECTIFIER.

Manufacturers : Dc Components

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DC COMPONENTS CO., LTD. R B05S THRU B10S RECTIFIER SPECIALISTS TECHNICAL SPECIFICATIONS OF SINGLE-PHASE MINI SURFACE MOUNT BRIDGE RECTIFIER VOLTAGE RANGE - 50 to 1000 Volts CURRENT - 0.5 Ampere FEATURES * * * * Surge overload rating - 30 Amperes peak Ideal for printed circuit board Reliable low cost construction Glass passivated junction DB-1MS MECHANICAL DATA * * * * * * Case: Molded plastic Epoxy: UL 94V-0 rate flame retardant Terminals: MIL-STD-202E, Method 208 guaranteed Polarity: Symbols molded or marked on body Mounting position: Any Weight: 0.22 gram .275(7.0)MAX .067(1.7) .057(1.3) .051(1.3) .035(0.9) .165(4.2) .150(3.8) .031(0.8) .019(0.5) .106(2.7) .09(2.3) .193(4.9) .177(4.5) .106(2.7) .09(2.3) .014(.35) .006(.15) .043(1.1) .027(0.7) .067(1.7) .057(1.3) MAXIMUM RATING [ ... ]

B4S PDF Datasheet Download