SPEC Stage 2+ is sprung and is rated at 545.
Wether thats lbs-ft or Nm they dont say....I dont know what to make of a manufacturer that doesnt give that info.
My guess is that its lbs-ft as it's an us brand and I can only imagine a US manufacturer be that unaware that there are more than 1 measuring unit and thus not saying what.
I cant imagine a german manufacturer (like sachs) to be that sloppy and unprecise in the engineering department.
You go to jail for that in Germany
But it's worth checking with the manufacturer what the actual spec is (not with some webshop, they dont know shit and just assume everything).
It's very affordable for a sprung aftermarket performance kit and they have a huge range (so even if it's Nm you can get a stronger one, they have so many)