What is the Comparison between 5oz flannel weight to 160gr flannel weight?

What you are asking is the difference between 5oz per square yard (Imperial) and 160grams per square meter (Metric).

1oz = 28.35 Grams

1yd = 0.91 meters

1yd2 = 0.836 Meters2

Therefore 1oz/Yd2 = 33.91g/M2

and 5oz/Yd2 = 169.55g/M2

or 4.72oz/Yd2 = 160g/M2

Assuming a resolution of +- 0.5 oz and +- 5 grams.

The answer is ... They are equivalent.

+- Marketing Hype and they mean nothing!!!