20/8/2021 · Southwire Emphasizes Sustainability Commitment with Declare Label Certification. May 11, 2021. Southwire recently obtained a Declare label for its 600 Volt and 1000 Volt SOLONONplus® Type XHHW-2 VW-1 cables, making it the first company in the U.S. to offer a Declare label for a power cable used in the wiring of green building projects.