S-threads, popularly known as Simu-Tunnels, were coordinated hyperspace matrices.
S-threads were extremely small Hyperspace tunnels used to ferry communications waves through. Due to their incredibly small dimensions, it was virtually impossible to intercept communications through an S-thread; the only way to do so was to attach a listening device to the Hyperwave transceivers responsible for managing information through the S-threads.
- "The Trouble with Squibs"—Star Wars Insider 67 (Mentioned only)
- Star by Star (First appearance)
- Vortex (Mentioned only)
- Cracken's Rebel Field Guide
- Imperial Sourcebook (First mentioned)
- Imperial Sourcebook, Second Edition
- Dark Empire Sourcebook
- The Movie Trilogy Sourcebook
- The Essential Guide to Weapons and Technology
- Visual Guides (Chapter 3, Image 17)
- Endor and the Moddell Sector"—Star Wars Gamer 9 "
- The Official Star Wars Fact File 85 (Homing Beacons)
- The Essential Atlas