This is what tirerack.com says for NT555RII​

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SELECTED SIZE​

• Size: 275/60R15
• Service Description:107V
• Load Index 107= 2,150 lbs (975 kg) per tire
  Speed Rating “V”= 149 mph (240 kph)
• Load Range:SL
• Max. Load= 2,149 lbs
  Max. psi= 51 psi
• UTQG:100 A A UTQG
• Max. Load:2,149 lbs
• Max. Inflation Pressure:51 psi
• Tread Depth:6.3/32"
• Tire Weight:30 lbs
• Rim Width Range:7.5-9.5"
• Meas. Rim Width:8"
• Sect. Width:11"
• Tread Width:9.2"
• Overall Diam.:28"
• Revs. Per Mile:742
• Country of Origin*:JPJP

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