what do they mean

[socalsnake]

Super Swamper TSL/SX
38x12.50-15 (Ply Rating=6 Tread Width=10 O.D.=37.4)what does 37.4 mean ????????????? whats 12.50

 

[BigOrange90Jimmy]

That's a rough measurement of what the outside diameter of the tire SHOULD be.

 

[k20]

the tire is 37.4" tall, the tread is 10" wide, and the 12.5 is sidewall to sidewall.