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Home Shop Cable Modems Cox Communications Motorola SB6121 4×4 Cable Modem
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Zoom 5345 DOCSIS 3.0 8x4 Cable Modem

Motorola SB6121 4×4 Cable Modem

Rated 4.71 out of 5 based on 14 customer ratings
(14 customer reviews)

$46.99 $40.99

  • 4×4 DOCSIS 3.0 Cable Modem Only – WiFi Router Sold Separately
  • Compatible with Time Warner, Charter, Spectrum, Cox, Cablevision & More!
  • Includes Support for IPv6 & Remote Management
  • 4×4 Channel Bonding Supports Wired Download Speeds up to 172 Mbps
  • Not Compatible with Comcast Xfinity

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  • Description
  • Additional information
  • Reviews (14)
  • About Arris
  • Shipping & Delivery
Description

Motorola SB6121 Product Details

The Motorola SB6121 DOCSIS 3.0 Cable Modem is compatible with Charter, Cox, Cablevision, Spectrum & Time Warner Cable. This model features a 4×4 channel bonded design that supports wired download speeds of more than 100 Mbps in each direction. This model has both a small physical footprint, but also was designed to conserve energy, making it one of the more “green” networking options available for your home.

 

Interface & Additional Features

The SB6121 cable modem features some of the best remote management features from Arris/Motorola. This model can be accessed online to manage settings, firmware, & more! These user-friendly diagnostics can help you diagnose connection issues, and prevents you from having to call your provider to your home to correct network problems. Additionally, this model provides the ability to provision and manage IP multicast and supports AES traffic encryption for enhanced security.

Additionally, this model supports IPv4 and IPv6 for enhanced network stability and security. Connect any wireless router for instant WiFi connections with all of your devices.

 

SB6121 Compatibility

This model has been tested & works great with Time Warner Cable, Spectrum, Cox, Cablevision & other US-Based cable providers. Since this model’s firmware is pretty versatile, even if you don’t see your provider listed here, it’s worth giving them a call to see if this model will work with your service. Always call before ordering, even if your provider is supported, to ensure that this model is a good fit for your location and service plan. Please note that this model is no longer approved for use with Comcast Xfinity.

What’s Included:

  • Motorola SB6121 Cable Modem
  • Ethernet Cable
  • Power Supply Cable
  • Online Installation Manual

Will this work with my internet company?

This Motorola modem is primarily used and is compatible with Spectrum, Time Warner Cable, Charter, Cox, & Cablevision service in most areas. To verify that this model will work in your area, always contact your service provider’s customer service prior to placing your order with us to confirm that this model will work with your service plan. Some service plan speeds may not be supported.

Additional information
Weight 1 lbs
Dimensions 9 × 6 × 3 in
Brand

Arris, Motorola

Model Number

SB6121

Condition

Grade A – Certified Renewed

Contents

Ethernet Cable, Modem, Power Cable

Interface

Cable Modem

Color

Black

Ethernet Ports

1-Port

DOCSIS Version

DOCSIS 3.0

DOCSIS Channels

4 x 4

Compatible Providers

Cablevision, Charter Spectrum, Cox Communications

Internet Plan

Sparklight 50

Reviews (14)

14 reviews for Motorola SB6121 4×4 Cable Modem

  1. Rated 5 out of 5

    EBeard – August 7, 2018

    Works as well as cable company rental, but much cheaper after 4 months. Four or five months rental paid for it. Now saving that money on cable bill.

  2. Rated 5 out of 5

    Christine – August 9, 2018

    I love it🤗🤗

  3. Rated 5 out of 5

    Kyle Trusler – August 10, 2018

    5 years later it’s still going strong. not sure what else to say about the modem. it’s just worked since day one. it’s nice and compact and light. saved me a ton of money not renting from $pectrum.

  4. Rated 5 out of 5

    stabby – August 10, 2018

    We have bought and returned three different modem/router combos in the past few weeks in setting up WiFi for our new house. This one is by far the best. We’ve had a great connection and no problems.

  5. Rated 5 out of 5

    Nanc’s notes – August 11, 2018

    This item is now saving me $125.00 per year from my cable company!!

  6. Rated 5 out of 5

    notsure – August 11, 2018

    works great. all the way across my apartment. PC via ethernet. super fast. and excellent connections via my phones and TV via WIFI all over the place.

  7. Rated 5 out of 5

    David Gomez – August 12, 2018

    Works great

  8. Rated 3 out of 5

    The Big Picture – August 12, 2018

    This modem works fine when it’s working. But sometimes it gives up and I have to power cycle it and the router to get things going again. This modem doesn’t play well with Zoom teleconferencing – e.g., calls will sometimes freeze up. The ARRIS technical support is the opposite of world-class; they’re too quick to say buy a new modem as well as not thoroughly knowledgeable about their own product. The online support files are mostly a mess and are way less than thorough. I’m hesitant to buy another of their products in the future. If I do, it’ll be with an extended warranty that’s easy to return the product if needed.

  9. Rated 5 out of 5

    Jtredway – August 12, 2018

    Works fine and does acceptable job to replace rented modems

  10. Rated 5 out of 5

    KAYE KEREKES – August 12, 2018

    Love it, works great

  11. Rated 5 out of 5

    JE – August 13, 2018

    Works ok, does what it should.

  12. Rated 5 out of 5

    Hailee – August 14, 2018

    Never have to reset it and have had no issues with our internet. Would recommend

  13. Rated 4 out of 5

    Ripley – August 15, 2018

    Works well. Had old one for 8 years

  14. Rated 4 out of 5

    O. Elfourgni – August 15, 2018

    Works but not capable of fast enough speed

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About Arris
Arris is a well-known manufacturer of internet modems and routers with over three decades of experience. The company was established in 1986 with an emphasis on offering new connectivity solutions for the telecommunications industry. Today, Arris is a prominent producer of broadband modems, routers, and gateways, with a reputation for producing dependable, user-friendly, and feature-rich devices of superior quality. Compatibility with a variety of internet service providers is a distinguishing characteristic of Arris's devices. The company's modems and routers are compatible with a range of technologies, including DSL, cable, and fiber, making them an excellent option for consumers seeking a flexible and dependable connectivity solution. Arris's devices are noted for their great performance in addition to their interoperability. The company's modems and routers are built to enable fast internet speeds and can handle massive volumes of data traffic, making them an excellent option for households with several internet-connected devices. Numerous Arris products include advanced technology such as Orthogonal Frequency Division Multiplexing (OFDM) and improved Quality of Service (QoS) for optimizing network performance and guaranteeing a seamless, dependable internet experience. Arris's devices are renowned for their usability in addition to their performance and interoperability. The company's modems and routers have user-friendly interfaces and straightforward setup procedures. Parental Controls and guest WiFi are included in a number of Arris's devices, making them an excellent choice for families and small companies. Arris is a reputable brand that offers a vast selection of high-quality, dependable, and feature-rich internet modems and routers. The company's solutions are compatible with a broad variety of internet service providers and are designed to accommodate high internet speeds and big volumes of data traffic. In addition, Arris's products are user-friendly and have helpful features like parental controls and guest WiFi.Motorola is a well-known company that has offered a variety of high-quality goods for more than ninety years. The company was started in 1928 with an emphasis on offering radio and technology markets with creative and dependable communication solutions. Motorola is a significant manufacturer of broadband modems, routers, and gateways, in addition to a vast array of other computer and technology products. The performance and dependability of Motorola's devices is one of its defining characteristics. Advanced technologies such as beamforming and Quality of Service (QoS) for optimizing network performance are incorporated into the company's modems and routers to ensure quick and dependable internet connectivity. In addition to their reliability and endurance, Motorola's devices are renowned for their high-quality construction and durability, which is achieved through the use of robust manufacturing techniques and materials. In addition to their effectiveness and dependability, Motorola products are renowned for their adaptability. The company's modems and routers are compatible with a range of internet service providers and technologies, including DSL, cable, and fiber, making them an excellent option for consumers seeking a flexible and dependable connectivity solution. Additionally, Motorola's products are available in a variety of sizes and designs to accommodate various demands and budgets, making them an excellent option for both home and small business users. In addition to performance, dependability, and portability, Motorola's products are renowned for their sophisticated capabilities and features. Many of the company's modems and routers offer VPN support, traffic control, and quality of service (QoS) for optimizing network performance, in addition to enhanced security technologies for protecting against online dangers. In addition to comprehensive management and monitoring capabilities, Motorola's devices include remote management, alarms, and diagnostics for monitoring network performance and diagnosing potential problems. Motorola is a reputable company that offers a vast selection of high-quality, dependable, and feature-rich goods. The company's modems and routers are designed to provide quick and dependable internet connectivity and are renowned for their adaptability, innovative features, and capabilities. Additionally, Motorola's devices are renowned for their superior construction, durability, and dedication to innovation and sustainability. In addition to modems and routers, Motorola is well-known for a variety of other computer and technology devices, such as switches, hubs, and adapters. Motorola is dedicated to providing its customers with the best possible experience and offers a choice of support alternatives to help them maximize their products. The company features a comprehensive online support area with an abundance of information, such as frequently asked questions, user guides, and firmware upgrades. Additionally, Motorola offers phone and email support for customers who require additional assistance or have more difficult concerns. Motorola is a reputable company that provides a vast selection of high-quality, dependable, and feature-packed products for both home and small business consumers. The company's modems and routers are designed to provide quick and dependable internet connectivity and are renowned for their adaptability, innovative features, and capabilities. Additionally, Motorola's products are renowned for their high-quality construction, durability, and commitment to innovation and sustainability, making them an excellent option for clients seeking a dependable and feature-rich connectivity solution.
Shipping & Delivery
When will my order ship?

We ship all orders within 1-2 business days from one of our US-based warehouses unless items in your order are on backorder. Backordered items are shipped as soon as they become available. If you've ordered an item that is backordered, we will email you to let you know as soon as possible.

Do you offer upgraded shipping options?

Check our shipping & delivery page for the most up-to-date information about shipping options. In most cases we offer standard shipping and an expedited shipping option.

What shipping carriers do you use?

We currently ship the majority of orders via USPS Priority Mail or Amazon Logistics. Larger orders are shipped with FedEx, UPS or LTL Freight. Please contact us if you have any questions regarding shipping to your location.

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