The Triumph Folding Door Track System combines an enclosed track with a 4-wheel carriage and sturdy steel pivot sets for a reliable folding door system. The fully sealed ZZ ball bearing wheels make for a quiet and smooth operation whilst the steel and brass pivots account for durability and reliability. The Triumph system is ideal for 2-4 doors in one direction but may also be used for up to 8 doors with the use of a bottom guide system.