Stage One BMW Speaker Upgrade for E90 Sedan with Standard Hi-Fi 4 SERIES not by checking the production

not by checking the production date of your vehicle chassis

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KIESMOTORSPORTS makes no guarantees to the legality of any parts used for “on highway vehicles” and accepts no responsibility for compliance with the vehicle’s factory warranty

Stage 2 93 octane: up to 18%HP / 24%TQ

Stage One BMW Speaker Upgrade for E90 Sedan with Standard Hi-Fi 4 SERIES not by checking the productionGET UNBELIEVABLE, CRYSTAL CLEAR SOUND. JUST BY REPLACING YOUR BMW'S SPEAKERS We took your factory BMW speakers and re engineered our upgrade for one thing: clarity. So you can simply swap your original speakers for ours without changing anything else in your audio system, and the result is smooth, natural, yet unbelievably detailed reproduction of your favorite music. PLAY YOUR MUSIC LOUDER. AND ENJOY EVERY NOTE: We engineered the Stage One speakers