This DB-35 disc brake rotor is zinc-plated and vented to help dissipate heat. This UFP product can be used with trailer axles that have are rated up to 3750 lbs, so it will work with the common 3500 lb axles, and they can be used with 13", 14", and 15" wheels. You get what you see in the pictures!                 

Spindle Size: 1-3/8" x 1-1/16" tapered
Diameter: 9-3/4"
Bolt circle: 5 on 4-1/2"
Inner Bearing: 1-3/8" (L68149) Not included
Inner Race: L68110 (Included)
Outer Bearing: 1-1/16" (L44649) Not included
Outer Race: L44610 (Included) 
Seal: 2.56" x 1.68" not included
Minimum Thickness: 17mm