Hella Horn Wiring Harness 02-14 WRX, 04-14 STI - GrimmSpeed Subaru; Hella Horn Wiring Harness 02-14 WRX, 04-14 STI; Hella Horn Wiring Harness 02-14 WRX, 04-14 STI. $29. SKU: 040005 Hella Horn Wiring Harness. Ordered this so that I would have a reliable harness for my horns that I ordered from Ebay. Couldn't be Subimods V4 Hella Horn Harness Kit Most Subaru Models Subimods V4 Hella Horn Harness Kit - 4 is the new 2 . Many customers do not realize that when you purchase a set of Hella Supertone Horns you will only receive a relay and some brief instructions on how the horns should be connected, some customers aren’t fully equipped to handle such a task others just don’t have the time to deal with making their own Wiring Harness from scratch.