pulley belt question

Ok, i bought an underdrive pulley but the mechanic said I need a different belt. For after sized pulleys, does one size belt fit all? it is for a 99 civic EX. does anyone know which belt i need?

most aftermarket pulley kits supposed to come with the belt too.. mines did

If you need an odd sized belt, get a tape measure, and wrap it around both pulleys to get the length you need. Then just go to a parts store and tell them what you need.