It's a heavy nylon belt I picked up at target or walmart I think. It's certainly not expensive.
I forgot to mention, I also always wear a knock off under armour sleeveless t shirt to keep the gun from rubbing me (even in the summer).
Spend the few extra bucks on a quality belt and see the difference. The one I bought is double bullhide with a kydex liner. Amazed at the weight and stiffness.