This is replacement Left and right rock sliders for model traxxas trx-4 all of series.Replacement part for these models:TRX-4® 1972 Chevrolet® Blazer® High Trail Edition™TRX-4® 1979 Chevrolet® Blazer®TRX-4® 1979 Ford® Bronco®TRX-4® Chevrolet® K10 High Trail Edition™TRX-4® Equipped with Traxx®TRX-4® ..