Electro Harmonix Intelligent Harmony Machine – Thomann United States
TC Helicon Harmony Singer 2 Vocal Processor at Gear4music
Boss PS-6 Harmonist Pedal with 3 Patch Cables | Sweetwater
TC-Helicon Harmony Singer Vocal Effects Pedal - Nearly New at Gear4music
Amazon.com: BOSS VE-2 Vocal Echo Pedal for Singing Guitarists | Real-Time Vocal Harmonies and Effects | Create Harmonies with Manual Key Selection | Connect Guitar for Auto Harmony Function | 24 Harmony