Some of us are still building hot rods with conventional style fan belts. Back in the day, parts stores had a whole wall of them, every size imaginable. I should know because my parents owned such a store in Alaska and I worked there. Guys building a new rod would come in and give us an approximate size needed. An hour later they'd be back needing one just an inch longer. Sometimes they'd return a third time. Never a problem! Stores today have limited inventory of V belts, with a mass array of boxed serpentine belts replacing them. Times have changed! I needed a 65 inch belt and our local stores didn't have it, but could order one. I asked if I could return and exchange for another if it didn't fit. The parts guy said no problem as long as I paid the shipping cost back. That's only right I suppose. I made sure my measurement was dead on using the right thickness of rope. Back in the day, guys used a piece of string to measure, thus the incorrect size belts. No biggie if they were wrong. The only expense was a gallon of gas driving back to the store. Dayco and Gates have always been my belts of choice. I saw a Chinese brand that I didn't recognize online the other day. Far as I know, Dayco and Gates are now manufactured there as well. In another twenty years, I'll hobble into a parts store and ask for a 65 inch belt, and the gal behind the counter will tell me, "We can't get those anymore. You might try one of the antique stores around town!"