300 series may refer to:

Japanese train types

• 300 Series Shinkansen
• Chichibu Railway 300 series electric multiple unit
• Choshi Electric Railway 300 series electric multiple unit
• HB-E300 series hybrid diesel multiple unit
• JR Freight Class HD300 hybrid diesel locomotive
• Meitetsu 300 series electric multiple unit

Other

• GeForce 300 Series family of graphics processing units
• Kodak DCS 300 series digital camera
• Rickenbacker 300 Series guitar
• Volvo 300 Series car
• 300 series, or austenitic stainless steel

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