Standard Ph1 Exhaust Diameter?

[lamborgini8]

Does anyone know the Diameter of the standard Mk2 Ph1 exhaust pipe? I would just go measure it but I can't seam to find anything to measure it with funny enough... Cousin stole my tools ¬_¬

 

[NWPerformance]

A 1.2 is 1 and a 1/4 inch i think