Sprocket Types #25, #35 etc

[joluc]

I'm new here so please bare with me.

I have a timing belt marked 130XL.  Figured out the 130 is the length and XL is the tooth profile at 5.08mm pitch.

Gearotic has a selection of Sprocket Types #25, #35 etc.  What do these mean? How do I know which are appropriate for my belt?  For a 2:1 ratio one sprocket will be twice the diameter of the other.  I did a web search and could find no useful tables with this info.

Thanks

[ArtF]

Hi:

Sprockets are different than the timing pulleys, sprockets use chains, while pulleys
use timing belts.  you want the section labeled "Pulleys" and to select XL as the type.
  You can then create as many teeth as you like.

Art