I haven’t weighed it to compare or find out, but according to their website, the new Krux frame looks like it’s now set up with the same frame sheet as the X Curve. So same material, only difference being the frame stays. The new Krux weighs 4 oz. Less than the X Curve. IME on the items I HAVE weighed, they don’t lie on the website. I’m guessing the difference is 4 ounces. I trust SG.
The straight stays are hollow, and the x curve stays are solid, but they’re both carbon. So it makes sense the Krux is a little lighter.
FWIW, I didn’t have them do it because I wanted to save weight. I wanted the Krux frame because their testing and fitting indicated that’s what I needed (no curve to my back), but they were out of the Krux Evo frame sheets at the time. So they offered to put the straight stays into the x curve frame sheet for me. Otherwise I would’ve just bought the Krux Evo frame at the time. It still Carrie’s weight like a boss though, I love the pack
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mismatched bag and frame colors and all haha