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2021 Audi A8 Quattro

Universal gear includes car amplifiers, subs, and other products that do not install in a specific location or require fitment to integrate with a vehicle.

Universal-Fit Audio for 2021 Audi A8 Quattro

When thinking of universal gear, we consider products like a car amp that gives more power to your speakers or subs, cell phone chargers, equalizers and sound processors, rear-seat entertainment and video monitors, as well as dash cameras.

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Single 12" Vented MDF Subwoofer Enclosure (Belva 1SV12B)

12-inch Vented Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.8 cu ft airspace 1SV12B)

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12-inch Vented Car Sub Box Made with 3/4" MDF and lined w/ Polyfil (1.8 cu ft airspace 1SV12B)

• Single 12" Vented MDF Enclosure
• Holds one 12" subwoofer
• 3/4 MDF (Medium Density Fiberboard) Construction
• Durable black carpeting
• Gold Terminals
• Internal Box Volume: 1.8 cubic ft.

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List price $95.99
-17% $79.99

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Stinger SPT521

Gauge Reducer, 1/0 Gauge Input to 4 Gauge Pin

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Gauge Reducer, 1/0 Gauge Input to 4 Gauge Pin

• Gauge Reducer Adapter
• 1/0 Gauge Input to 4 Gauge Pin
• Deep Wire Recesses
• Ultimate Power Delivery
• Corrosion Resistant Shoc-Krome Plating

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List price $29.00
-55% $12.99

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• Gauge Reducer Adapter
• 1/0 Gauge Input to 4 Gauge Pin
• Deep Wire Recesses
• Ultimate Power Delivery
• Corrosion Resistant Shoc-Krome Plating

AudioControl MATRIX PLUS

6-Channel Line Driver with Optional Level Control

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6-Channel Line Driver with Optional Level Control


• Active 6-Channel Line Driver
• Increase pre-amp signal levels up to 9.5 volts RMS
• Matches the volume levels between different sources
• Two channels of input can drive all six outputs
• Each output can drive up to seven amplifiers

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List price $339.00
-27% $249.00

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• Active 6-Channel Line Driver
• Increase pre-amp signal levels up to 9.5 volts RMS
• Matches the volume levels between different sources
• Two channels of input can drive all six outputs
• Each output can drive up to seven amplifiers

Viper 5308V

2-Way Remote Start Keyless Entry System with 4-Button Transmitter

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2-Way Remote Start Keyless Entry System with 4-Button Transmitter

• 2-Way 5-Button Remote Car Starter
• With 4-Button Transmitter
• 1320 feet Range
• Antenna With Integrated Valet Switch & LED
• Built-in security features

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List price $379.99
-16% $319.99

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Ships in 10-14 days

• 2-Way 5-Button Remote Car Starter
• With 4-Button Transmitter
• 1320 feet Range
• Antenna With Integrated Valet Switch & LED
• Built-in security features

Stinger SPT522

Gauge Reducer, 4 Gauge Input to 8 Gauge Pin

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Gauge Reducer, 4 Gauge Input to 8 Gauge Pin

• Gauge Reducer Adapter
• 4 Gauge Input to 8 Gauge Pin
• Deep Wire Recesses
• Ultimate Power Delivery
• Corrosion Resistant Chrome Plating

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23
List price $19.00
-47% $9.99

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Only 1 Left!

• Gauge Reducer Adapter
• 4 Gauge Input to 8 Gauge Pin
• Deep Wire Recesses
• Ultimate Power Delivery
• Corrosion Resistant Chrome Plating

Limited time!

Belva BATENT1

Single Knob Surface Mount Housing for use with BAWPL, BA2USB, BAVTM

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Single Knob Surface Mount Housing for use with BAWPL, BA2USB, BAVTM

• Single Knob Surface Mount Housing Pod
• For use with Belva BAWLK, BA2USB or BAVTM

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List price $3.99
-50% $1.99

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• Single Knob Surface Mount Housing Pod
• For use with Belva BAWLK, BA2USB or BAVTM

Omega DS-2.4

Economy Door Lock Actuator

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Economy Door Lock Actuator

• Single Door Lock Actuator
• Converts Manual Doorlocks Into Power Doorlocks
• Two-Wire Reverse Polarity Operation
• Universal Mounting Hardware Included

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List price $19.99
-40% $11.99

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• Single Door Lock Actuator
• Converts Manual Doorlocks Into Power Doorlocks
• Two-Wire Reverse Polarity Operation
• Universal Mounting Hardware Included

Audiovox FMDIRB

FM Modulator Relay Box and Direct Adapter

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FM Modulator Relay Box and Direct Adapter

• Converts internal wireless FM transmitter to a wired FM modulator
• Connects audio output with POD with FM modulator to car radio
• Designed for use with Audiovox SIRCK3 and XC9 vehicle kits

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$39.99

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Ships in 10-14 days

• Converts internal wireless FM transmitter to a wired FM modulator
• Connects audio output with POD with FM modulator to car radio
• Designed for use with Audiovox SIRCK3 and XC9 vehicle kits

PAC BB-1PR

Pair of Bass Blocker / Passive Crossover; Removes 0-300Hz at 4 ohms, 0-150Hz at 8 ohms (BB1PR)

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Pair of Bass Blocker / Passive Crossover; Removes 0-300Hz at 4 ohms, 0-150Hz at 8 ohms (BB1PR)

&bull Pair of Bass Blockers for 6" x 9" Speakers
• Blocks 0-300Hz @ 4 Ohm
• Blocks 0-150Hz @ 8 Ohm
• Filters Out Unwanted Frequencies Towards Speakers

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-45% $15.99

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&bull Pair of Bass Blockers for 6" x 9" Speakers
• Blocks 0-300Hz @ 4 Ohm
• Blocks 0-150Hz @ 8 Ohm
• Filters Out Unwanted Frequencies Towards Speakers

JL Audio CL-RLC

2-Channel Remote Level Control and Line Driver Preamplifier

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2-Channel Remote Level Control and Line Driver Preamplifier

• Fully Active, 2-Channel Remote Level Control and Line Driver with Pass-Through Outputs
• Minimizes Unwanted Noise
• Active Circuitry
• Control Knob
• Pass-Through Connection

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$89.99

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Ships in 10-14 days

• Fully Active, 2-Channel Remote Level Control and Line Driver with Pass-Through Outputs
• Minimizes Unwanted Noise
• Active Circuitry
• Control Knob
• Pass-Through Connection

Stinger SGP90200

200 Amp Circuit Breaker

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200 Amp Circuit Breaker

• 200 Amp Circuit Breaker
• Dust and splash proof
• Accepts 1/0 or 4 gauge wire
• Easy reset/disconnect
• Can act as a master disconnect for circuits

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List price $139.00
-50% $68.99

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Only 1 Left!

• 200 Amp Circuit Breaker
• Dust and splash proof
• Accepts 1/0 or 4 gauge wire
• Easy reset/disconnect
• Can act as a master disconnect for circuits

Tru Spec Dual 12in P (1460YX)

Empty Dual 12" Vented Prefabricated Enclosure for Sundown SA 12" Subwoofers

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Empty Dual 12" Vented Prefabricated Enclosure for Sundown SA 12" Subwoofers

• 12" Dual Ported Subwoofer Enclosure
• 3/4" Medium Density Fiberboard (MDF) construction
• Total box volume: 3.50 cubic feet
• Compatible for Sundown SA 12V2 subwoofers (Sold separately)

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6
List price $299.99
-22% $234.99

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Stinger SPI300

600W Peak (300W RMS) Dual Outlet Portable Power Inverter

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600W Peak (300W RMS) Dual Outlet Portable Power Inverter

• Dual Outlet Portable Power Inverter
• Surge Power Output: 600 watts
• Continuous Power Output: 300 watts
• USB port included for charging compatible devices
• Internal cooling fan keeps the inverter from overheating

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-74% $43.99

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• Dual Outlet Portable Power Inverter
• Surge Power Output: 600 watts
• Continuous Power Output: 300 watts
• USB port included for charging compatible devices
• Internal cooling fan keeps the inverter from overheating

AudioControl PNW-XN3

3-way Passive Crossover Network

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3-way Passive Crossover Network

• 3-way Passive Crossover Network
• Designed to expand a 2-way component system into a 3-way setup
• Ideal for adding a midrange driver to your 2-way component system
• Includes woofer, midrange and tweeter outputs
• Compatible with AudioControl PNW and Altitude Series speakers

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List price $179.00
-11% $159.00

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• 3-way Passive Crossover Network
• Designed to expand a 2-way component system into a 3-way setup
• Ideal for adding a midrange driver to your 2-way component system
• Includes woofer, midrange and tweeter outputs
• Compatible with AudioControl PNW and Altitude Series speakers

NVX XIV25

16.4 ft (5 meter) 2-Channel V-Series RCA Audio Interconnect Cable

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16.4 ft (5 meter) 2-Channel V-Series RCA Audio Interconnect Cable

• Shielded noise-rejecting Twisted-pair construction
• Heavy gauge OFC conductors ensure superior sound quality
• Split-tip Silver-Plated ends offer best in class signal transfer
• Molded ends equipped with colored channel identifiers

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-32% $12.99

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• Shielded noise-rejecting Twisted-pair construction
• Heavy gauge OFC conductors ensure superior sound quality
• Split-tip Silver-Plated ends offer best in class signal transfer
• Molded ends equipped with colored channel identifiers

NVX XQDC4

4 AWG High Current Power and Ground Quick Disconnect with Surface Mounts

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4 AWG High Current Power and Ground Quick Disconnect with Surface Mounts

• 4 AWG Power, Ground and Remote Quick Disconnect
• Rated up to 120 Amps
• Anderson connectors
• Makes it easy to remove amps, batteries and other equipment quickly
• Includes male and female quick disconnects

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List price $27.99
-7% $25.99

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Used from: $15.59 Like New from: $22.09

• 4 AWG Power, Ground and Remote Quick Disconnect
• Rated up to 120 Amps
• Anderson connectors
• Makes it easy to remove amps, batteries and other equipment quickly
• Includes male and female quick disconnects

T-Spec VBTPN

(4) 0 Gauge or (4) 4/8/10 Gauge outputs with bolt-on post for factory harness retention

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(4) 0 Gauge or (4) 4/8/10 Gauge outputs with bolt-on post for factory harness retention

• For positive or negative battery post use
• Add a Post System
• >Solid brass construction

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• For positive or negative battery post use
• Add a Post System
• >Solid brass construction

Belva BBSW127

12 Gauge 7 Meter (23 Ft) Speaker Wire (CCA)

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12 Gauge 7 Meter (23 Ft) Speaker Wire (CCA)

• 7 Meters
• 12 Gauge Speaker Wire
• High Strand Count for Maximum Flexibility
• 23 Foot Length

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• 7 Meters
• 12 Gauge Speaker Wire
• High Strand Count for Maximum Flexibility
• 23 Foot Length

JL Audio SGRU-12

Mesh Grille for JL Audio 12" W0v3, W1v3 and W3v3 Subwoofers

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Mesh Grille for JL Audio 12" W0v3, W1v3 and W3v3 Subwoofers

• 12" Grille made specifically for the JL Audio 12W1v2, 12W3v3, or 12TW5 Sub
• Provides the Best Protection Possible
• Top-Notch JL Audio Quality
• Metal Mesh Grille Painted Black

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$49.99

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• 12" Grille made specifically for the JL Audio 12W1v2, 12W3v3, or 12TW5 Sub
• Provides the Best Protection Possible
• Top-Notch JL Audio Quality
• Metal Mesh Grille Painted Black

NVX XKIT44

Full Spec 4 Gauge 100% (OFC) Oxygen Free Copper Complete 4-Channel Amplifier Wiring Kit with RCA for Amplifiers up to 1500 Watts

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Full Spec 4 Gauge 100% (OFC) Oxygen Free Copper Complete 4-Channel Amplifier Wiring Kit with RCA for Amplifiers up to 1500 Watts

• Complete 4 Gauge Amplifier Installation Kit
• For Amplifiers Up To 1500 Watts RMS
• 100% (OFC) Oxygen Free Copper
• Dual Twisted Pair 4-Channel RCA Cable
• Tinned conductors for corrosion resistance
• Pre-terminated seamless power and ground ring terminals
• ANL/Mini-ANL Fuse Holder with 100 amp fuse
• CEA-2015 and BC5W2 Compliant

4+ offers available
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Available Offers (4) for NVX XKIT44
FREE NVX Amp Kit at Checkout!
Save 30% off an NVX XKIT44 Amp Kit at Checkout! Add a qualifying amplifier to your cart and save 30% on the NVX XKIT44 Amp Kit! No code needed — discount applies automatically at checkout.
15% off an NVX XCAP10H w/ Select Amp Kits Add a qualifying amplifier to your cart and save 15% on the NVX XCAP10H Capacitor! No code needed — discount applies automatically at checkout.
15% off an NVX XCAP1F w/ Select Amp Kits Add a qualifying amplifier to your cart and save 15% on the NVX XCAP1F Capacitor! No code needed — discount applies automatically at checkout.
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    FAQ for Universal-Fit Audio & Electronics in 2021 A8 Quattro

    Q: Can I upgrade or change the Universal-Fit Audio & Electronics in 2021 Audi A8 Quattro?

    A: Yes this page includes all the best Universal-Fit Audio & Electronics that work in your A8 Quattro.

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    Modern vehicles often require specific brackets, wiring harnesses, and mounting solutions. A fit guide ensures:

    • You see only parts engineered for your exact vehicle
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    Whether you're replacing a factory stereo or upgrading your entire audio system, the Fit Finder eliminates uncertainty.