Plain connectors are traditionally used where there is a track connection, but no access directly above the area to use a mount system or support.
For example, a threaded rod connector implies that the connection between two curtain track sections has a structural attachment point directly above it. The plain connector joins the track sections and is used with split supports, which allow the attachment points to accommodate irregular attachment point distances.
We recommend a support attachment every 5 feet to secure your curtain wall track system. The split supports can attach at any given point along the track section to insure the complete curtain wall system is supported properly.