Can that rod be that light? It could...
I would have to put one on my scale to believe it. More likely it is under 3 oz.
I wouldn't be surprised if the reelseat and insert alone weigh at least an ounce. Cork grips are light, but not weightless, figure 0.4 oz. Even in unidirectional S2 glass I would expect the rod blank to weigh about an ounce. Guides, glue, finish don't weigh a lot, but again they aren't weightless. The numbers add up. Perhaps the cork filler is made with helium filled microbubbles?
I have weighed many rods over the years. Very few matched the numbers printed in the catalog or on the rod. Most were heavier. One of the very, very few that broke 2 oz was the 6'8" St. Croix 7090 XXL. It is the second rod down in the photo. The grip is very slender and the reelseat is two extremely light weight rings. That rod weighs 1.75 oz - with 1970s technology.