The total weight for Skjold 10 UL is 520 g / 18,3 oz. The normal Skjold 10 has a total weight of 655 g/ 23 oz.
Skjold UL has a bright blue color (midnight blue), while Skjold 10 comes in Dark Grey and Camo.
Both tarps are solid and waterproof and they are manufactured in the same way. Skjold UL is made of a slightly thinner fabric but is nearly as robust as Skjold 10.
Make your choice based on weight, packed dimensions, and color.