1350 vs Crate D21

[money17]

What is difference other than one is blocked and one is not?

[MasterSbilt_Racer]

Spec 1350 or economy? We are talking construction differences for the economy. I don't believe the rubber is the same either way.

[a25rjr]

Are you talking about a standard d21 or a crate/usa 21?

[money17]

Crate d21 vs 1350 white dot on right rear.