ATI PERFORMANCE SUPER DAMPER Harmonic Damper [OUTER DIAMETER 8.53 (14% OD) | WEIGHT 11.5 LBS | SHELL MATERIAL ALUM | RIBS 11 | 6 RIB REAR PULLEY | HUB MATERIAL STEEL] (GM LS9) : COLORADOSPEED - LATE MODEL DOMESTIC (AMERICAN MUSCLE) | IMPORT (EUROPEAN | SPORT COMPACT) AUTOMOTIVE PERFORMANCE PARTS