Wall Track provides a common interface for mounting multiple Ergotron components. • 26 Mounting track for most vertical surfaces click her for 10 Wall Track 34 Wall Track and 42 Wall Track. • One wall track mount bracket kit is needed to attach each arm and pivot to wall track. Use this bracket for LX and MX arms 400 200 and 100 arms. Also for attaching Universal CPU holder or Utility Shelf. • Wall track mounting kit is needed for attaching the track to wall; 97-531 for metal or wood studs 90-011 to attach track to hollow walls. • Track mount bracket kit for CPU is needed to attach the Vertical CPU to wall track. • Cable management channel covers - included. • Sold as 1 Each.