Note: It is a good practice to ALWAYS keep an extra Belt and Pulley Kit in your Air Cooled VW just in case of an Emergency. People new to aircooled Type 1 engined VWs often do not realize that the fan belt drives the cooling fan. Broken fan belt = no fan = no cooling = engine overheating and total meltdown within minutes or even seconds on a hot day.
To test the belt for proper tension, press firmly on the belt with your thumb at about halfway between the Generator Pulley and the Crank Pulley. The Belt should yield approximately 15mm or 5/8" if it is set correctly.
EMPI