Kicker KPX- Series Marine & Power Sports Full Range Amp 300-W 4-CH | 5 — Big Jeff Online Inc
Skip to content
Free shipping with delivery in 2-4 days See details
Free shipping with delivery in 2-4 days See details



Kicker KPX- Series Marine & Power Sports Full Range Amp 300-W 4-CH | 51KPX3004

SKU KI-51KPX3004
Sold out
Original price $437.48
Original price $437.48 - Original price $437.48
Original price $437.48
Current price $319.99
$319.99 - $319.99
Current price $319.99
Snap Logo Lease for as low as $/week Learn More

Free Gifts when added to Cart

The more you spend, the greater selection of free gifts you'll have at your fingertips when selecting items in your shopping cart!

Spend More, Save More

Big Jeff loves his customers!!!
  • Spend $250, Save 3%
  • Spend $500, Save 5%
  • Spend $1000, Save 10%
  • Spend $1500, Save 11%
  • Spend $2500, Save 12%
  • Spend $5000, Save 15%

*Does not apply to: AudioControl, Avatar, Deaf Bonce, Sundown, XS power or Kicker products*

*Does not stack with other promotional sales*

  • Compact Powerhouse: The KPX 300watt 4-Channel Amplifier packs a punch in a remarkably compact footprint, making it ideal for motorcycles, ATVs, and other space-compromised installations while delivering up to 300-plus watts of power.
  • Versatile Speaker Support: Designed to power every speaker in your ride, this amplifier is perfect for two- or four-speaker systems, ensuring incredible sonic performance and long speaker life even in extreme conditions.
  • Weather-Resistant Design: Built to withstand the elements, this weather-resistant amp is engineered to endure the rigors of outdoor use, providing reliable performance no matter where your adventures take you.
  • Customizable Sound Control: With built-in crossover controls and independent gains, you can easily fine-tune your audio system to achieve the perfect sound. The variable 12dB crossover and selectable electronic crossover offer flexibility to match your preferences.
  • Wide Compatibility: With a wide range of input levels, this amp is easy to hook up with virtually any factory or aftermarket radio, providing seamless integration and compatibility for hassle-free installation.
  • High-Quality Performance: Enjoy clear, powerful sound reproduction with RMS Power Output ranging from 45W x 4 @ 14.4V 4-Ohm stereo to 150W X 2 @ 14.4V 4-Ohm mono, ensuring exceptional audio performance for your outdoor adventures.

Kicker KPX- Series Marine & Power Sports Full Range Amp 300-W 4-CH | 51KPX3004

This Listing Includes:

  • (1) Kicker KPX 300watt 4-Channel Amplifier.

Big System. Little Amp.

  • Extremely compact footprint

  • Provides power for two- or four-speaker systems.

  • Up to 300-plus watts of power.

  • Fits under motorcycle fairings.

  • Weather-resistant design.

  • Built-in crossover controls.

The KPX300.4 Four-Channel Amplifier is built to power every speaker in your ride. Engineered specifically for motorcycles or space-compromised installs, this weather-resistant amp delivers huge power without getting in your way. Ensuring incredible sonic performance and long speaker life has never been easier with a variable 12dB crossover and independent gains. A wide range of input levels make this amp easy to hook up with virtually any factory or aftermarket radio.

This KPX300.4 Amplifier delivers as much as 75 watts per channel (4 channels driven), or 150 watts into two sets of bridged channels. See below for details.

Technical Specifications:

  • Dynamic Power: 350W

  • RMS Power Output: @14.4V

  • 14.4V, 4-Ohm stereo, < 1% THD+N: 45W x 4

  • 14.4V, 2-Ohm stereo, < 1% THD+N: 75W x 4

  • 14.4V, 4-Ohm mono, < 1% THD+N: 150W X 2

  • Frequency Response [Hz]: 20Hz – 20kHz

  • Selectable Electronic Crossover: 12dB/Octave  Hi-Pass 60/80/120 Hz

  • Fader On/Off Switch: Yes

  • Signal-to-Noise Ratio [dB]: >90dB, a-weighted, re: rated power.

  • Signal-to-Noise Ratio [dB]: >75dB (ref: 1W output)

  • Input Sensitivity: Low Level: 125mV-5V || High Level: 1V–40V


  • Length: 8 1/2" = 21.7cm

  • Height: 1 1/16" = 4.3cm

  • Width: 3 5/16" = 8.4cm

Payment Information


We accept PayPal for all ebay orders. You can use your credit through PayPal as all major credit card are accepted by PayPal.

We accept PayPal for all international orders, your address must be verified with PayPal.

We are not responsible for any custom duties or brokerage fees that may apply for all international orders.

When you click on the Buy it Now button you are entering into a
contract whereby you agree to purchasing the item at the price listed.

If you want to ship your item to an alternate address please add
that address on your PayPal account and use the address as the default
or confirmed address to pay us through PayPal

With Free Same Business Day Shipping we work to get you your order Fast. 


All orders over $500 will require a signature for delivery.

All pre-selected shipping rates and methods are for customers with a
valid residential or commercial address within the Contiguous 48 United
States (PO Boxes address may require additional charges).

P.O. Boxes, APO/FPO addresses, Alaska, Hawaii, Puerto Rico, Guam,
U.S. Virgin Islands, Northern Mariana Islands, American Samoa, Canada,
and other countries may require additional shipping fees. Please contact
a member of our team for detailed shipping charges.

Shipping is available only to PayPal verified addresses. When making
payment please confirm your address has been verified with PayPal. Once
payment is made shipping address can not be changed/altered. Payments
made using an unverified PayPal address will be refunded and order will
be canceled.

We will not accept request to change shipping address once payment
has been made. Please confirm your shipping address is up-to-date and

Typical handling time for orders is 1-business day. We do our best
to ship every package with-in 1 business day of receiving a cleared
payment. In some circumstances additional time may be need, in which
case we will contact buyer.

Shipped orders that are returned by the shipping company due to an
insufficient address or an undeliverable address will be refunded less a
20% restocking fee.

If package is refused or marked undeliverable and returned
back to us by the carrier, you will need to pay the shipping cost in
full to have the package sent back to you or we can refund the money
minus the cost of shipping


If you have not received your package, but the tracking information shows that it was delivered,
please do the following within 36 hours of expected, stated delivery:


Verify the shipping address on the order is the address where you are looking for the package

Look for a notice of attempted delivery

Look around the delivery location for the package, or see if a neighbor has accepted the delivery

Be sure to double check your mailbox and other usual spots for package delivery


If you think that your package has been stolen, we will require a police report since this is now theft.
Once we have a police report on file for the stolen package, we will reship your order.

Customer Reviews

Be the first to write a review