A preset on a Line 6 Helix or HX Stomp is a saved guitar rig: an amp, a speaker cabinet, the pedals in front of them, the order it all runs in, and where every knob is set. Line 6 saves one as an .hlx file. This gem opens that file and hands the rig back as ordinary Ruby - the blocks in order, what each one is, and every setting - so you can read a preset, compare two, or index a library of them. No hardware needed. The file is parsed by the same Rust code that talks to the pedal itself, so it reads here exactly as it does there.