IMPORTANT: Electrical items are covered by a 30 day EXCHANGE ONLY WARRANTY. There are no returns or refunds on such items.Introduced as an emission reduction device for numerous vehicles in the 1970s, the transmission controlled spark system restricts vacuum advance when the engine is operating at its normal temperature. For 1971 Chevrolet C/K pickup trucks as well as Blazer and Suburban models of the same year, this transmission controlled spark harness is important for maintaining factory performance.
| Make | Model | Years |
| Chevrolet | Blazer | 1971 |
| Chevrolet | C10 Pickup | 1971 |
| Chevrolet | C10 Suburban | 1971 |
| Chevrolet | C20 Pickup | 1971 |
| Chevrolet | C20 Suburban | 1971 |
| Chevrolet | C30 Pickup | 1971 |
| Chevrolet | K10 Pickup | 1971 |
| Chevrolet | K10 Suburban | 1971 |
| Chevrolet | K20 Pickup | 1971 |
| Chevrolet | K20 Suburban | 1971 |
| Chevrolet | K30 Pickup | 1971 |
