THE MARGIN / STOCK SUPPLY INDEX
Read the specification
Can I treat A4 and US Letter as the same paper size?
Keep exact paper format and machine/document settings aligned.
Does 80 gsm tell me the paper thickness?
Distinguish grammage from caliper and printer-path requirements.
Can I compare CIE whiteness and ISO brightness as one number?
Retain metric,method and exact version before comparing appearance claims.