3B

3B or 3-B may refer to:

• Third baseman
• Triple (baseball)
• 3B Computers, a range of computers produced by AT&T during the 1980s
• 3B Junior, a department of the Japanese entertainment company Stardust Promotion
• 3B Lab, a Japanese popular music group
• Three Bs, a designation for three well-known classical composers
• 3B, a very soft grade of pencil lead

{{overbar|3B}} may refer to:

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