Corrections are the most useful thing you can send. If a number here disagrees with a supplier data sheet, or a page reads a measurement the way you did not mean it, say so and include what you typed.
Every constant on this site carries a note saying where it came from, so a correction can be checked against the same source. Quantities that differ from a supplier's own figure are worth a message even when the arithmetic looks right: a bag yield or a coverage rate can change between production runs.