400 pounds is the limit to the weight of the person or persons. They will pick up 1000+ pounds. But a 400 pound person can put more than a 400 pound load on a suspension, especially if it is strung tight. Honestly there aren't many hammocks that are rated for 400 pound people.
Interesting i've never seen weights listed in this manner, usually they are listed with the maximum strength of the device, not the weight of the person. Ordered 2 pairs.