Hi Glide Support Rails are manufactured from structural grade aluminium ensuring a strong yet lightweight system. The rails are supplied in pairs & are available in lengths of 2m, 3m & 4.5m. You will need at least two rails to be fixed to the ceiling of your studio, the fixed rails will support the floating rails which will support your lighting equipment. A Joining Plate can be used to increase the length of fixed rails or to join together a perimeter track. The Joining Plate cannot be used to lengthen floating rails.