The NU-Cable is a proprietary cable system. 
From the manufacturer's website:
The NU-CABLE High Tension Cable Barrier System offers a unique combination of TL-3 and TL-4 crash-test proven protection and visual appeal in both median and right-side guide rail applications. Plus the added bonus of a 50 to 75% cost saving versus traditional W-beam and concrete barriers, and up to 20% savings over other high-tension cable systems.
Key features of the NU-Cable system are: