A-Team Performance 170072 HEI Distributor Battery and Tachometer Pigtail Harness 12V Wire Connection Guide: Color coded, Easier to Identify the Tachometer and Battery Connections - The Green Wire is for the Tachometer, the Red Wire is for the Battery. Locking tab and shark fin design, ensure a tight positive fit and a reliable connection between the wiring and HEI. Made of high temperature plastic rated at more than 250 degrees. Two 7" leads for easy installation and a clean connection.