Zilker Belts ATX DarkWorld class dark brown Argentine leather orange & white nylon thread, artfully hand stitched in Buenos Aires. DONT KNOW YOUR SIZE? A good rule when choosing a Zilker Belt is to go 2 larger than your pants' waist size. So if you typically wear size 34 jeans, order a size 36 belt. For odd sizes, we suggest ordering 3 larger to be safe (ex. choose a size 38 Zilker Belt for size 35 jeans).