Hi
I hope you can help me.
In a recent article in a french magazine someone write that G4 was the best to hardened and impreabilize(?), (ok make it water proof paper), cardboard, etc.
I must believe this is true because I never tried it before.
Even more I don't know what is it.
Is, someone, out there,that could enlighten me about this G4? please.
Best regards from Portugal
Pedro Alves da Silva