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ARRIS

ARRIS SURFboard SB6121 4x4 DOCSIS 3.0 Cable Modem (Renewed)-Black

    • Based on 771 reviews
Condition: Excellent Condition (Refurbished)
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$37.81 Why this price?
Save $62.18 was $99.99

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This item is eligible for return within 30 days of receipt

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, May 20
Order within 7 hours and 49 minutes
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Features

  • This Certified Refurbished product is manufacturer refurbished, shows limited or no wear, and includes all original accessories plus a 90-day warranty. IMPORTANT NOTEL: A few units might show the brand as Motorola (and not Arris) as Arris had acquired Motorola for 2 years; hence it will be the same product and the same model
  • Requires CABLE Internet Service, if not sure your provider is CABLE call them to confirm. Does NOT work with Charter cable provider.
  • Compatible with MOST Major CABLE providers like Comcast/Xfinity, Cox, Time Warner, Mediacom, Bright House.
  • Wired modem only, does NOT include WIFI Router or VOIP Telephone adapter. Gigabit Ethernet port to connect to computer or Router for fast downloads.
  • Internet download speeds up to 172 Mbps and upload speeds up to 131 Mbps based on your Cable provider service. Good for streaming Video and gaming on multiple devices at a time.

Description

A new and improved version of the world's most widely deployed DOCSIS cable modems. For the residential cable subscriber who wants a powerful modem capable of delivering a high-speed data service at blazing fast speeds.10 / 100 / 1000 Base-T Ethernet Port (RJ-45). Requires CABLE Internet Service, if not sure your provider is CABLE call them to confirm Compatible with ALL Major CABLE providers like Comcast, Cox, Charter, Time Warner, Mediacom, Bright House Building upon the success of the SB6120, Motorola's SURFboard SB6121 delivers your complete personal media experience, at lightning-fast broadband speed. It harnesses the power of DOCSIS 3.0 technology to bond up to four downstream channels and four upstream channels--providing you advanced multimedia services with data rates of more than 100 Mbps in each direction. That makes gaming, shopping, downloading, working, high-quality voice and video conferencing, and peer-to-peer networking applications far more realistic, faster, and efficient than ever before. The SB6121 is compatible with the following operating systems: Windows 7 Windows Vista, Service Pack 1 or later Windows XP, Service Pack 2 or later Mac 10.4 or later (Ethernet connection only) UNIX (Ethernet connection only) Linux (Ethernet connection only) Please understand that the Arris/Motorola Certified Refurbished Modem you are purchasing may have been previously set up with your Cable Internet Provider. We make the best effort to ensure the MAC ID is purged from that Provider’s database as part of the refurbish process, BUT occasionally they are not. If you get one that can NOT be activated due to the MAC ID, then please email Arris/Motorola and they will promptly exchange your modem.


Brand: ARRIS


Internet service provider: Cox_communications, Xfinity_from_comcast


Connectivity Technology: Ethernet


Compatible Devices: Personal Computer


Item Dimensions LxWxH: 2 x 6.4 x 8.7 inches


Brand: ‎ARRIS


Item model number: ‎SB121


Item Weight: ‎1.2 pounds


Product Dimensions: ‎2 x 6.4 x 8.7 inches


Item Dimensions LxWxH: ‎2 x 6.4 x 8.7 inches


Color: ‎Black


Manufacturer: ‎Arris


Is Discontinued By Manufacturer: ‎No


Date First Available: ‎March 15, 2015


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, May 20

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • PayTomorrow Financing
  • Apple Pay Later
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

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Top Amazon Reviews

    • Saves money, works better than the cable company's modem
I've had Time Warner Internet for a couple of years and finally got sick of the fact that the company charges customers through the nose for the stupid modem it provides. $10 a month as a "rental fee" for such a simple piece of technology is outrageous, and I rue the fact that I paid TWC in excess of $250 because I was too lazy to do anything about it. Well, no more. The Arris SURFboard will have paid for itself by month 5. On top of that, my go-to Internet guy told me the Arris modem has better/faster technology on board than the TWC box did. An extra benefit was that when I called TWC to get the modem registered on its network — which was surprisingly easy and not too time-consuming — the rep offered to upgrade my speed from 20Mbps to 50 Mbps, for free (caveat: they may start charging in a year). I just tested my speed and am actually getting 60Mbps on average now. That wouldn't have happened if I hadn't purchased the Arris. Happy surfing! ... show more
Reviewed in the United States on March 8, 2016 by TerryF
    • A good little modem
I'm with Spectrum & got tired of being charged $10 extra for their modem. So, I went with the ARRIS SURFboard SB6121 & have been happy so far. My old modem was almost twice as big & I'm happy my new modem takes up less space. The install instructions make it sound like it is plug & play. Nope. But you do need get to it all set up before calling your cable company. They will want this number called a HFC Mac # that is usually found on the label on the back or bottom of the modem. Get that number before setting up & calling. It saves you scrambling around trying to find it & having to flip up your modem after it's all wired up :) Which is what happened to me, btw. It took just a few minutes after I gave the tech that number before I was online. ... show more
Reviewed in the United States on January 22, 2023 by Susan K. Nagata
    • Works Great with Comcast
The box says refurbished, but looks new to me. Came with protective plastic on the front bezel, instructions, cable, power adapter. Best of all, it fired right up and Comcast cable had no problem provisioning it. What else can I say. I works like it was supposed to work. If you are not familiar with cable modems, here are a few things you should know before you lay out your money for one. This type modem is NOT a ROUTER, you will need one if you want any kind of firewall at all between the outside world and your computer. You may also want an Ethernet hub because this modem has only one Ethernet port on the back which is meant to go from the box to your computer and that is it. Since most households now have Smart TV, Smart Phones, Smart Refrigerators etc... these devices all require a wireless internet link. This cable modem does not provide any wireless link. That is something you must furnish as well. I have my cable modem hooked up directly to a wireless router. Then I have one Ethernet port on the router connected to an Ethernet hub to connect other computers to the network known as hard wired. The wireless router takes care of all the wireless devices in the household. Is it worth it? Yes! Why pay 10 bucks plus tax or more a month to rent this same equipment from your cable provider when you can buy it and have it pay for itself in six months time? That part is a no brainer. What if it breaks? will my cable company fix it? No. When was the last time remember a cable modem broke, outside of a house fire or other disaster? If it breaks, you buy a new one and have it delivered to your home in two days or less by Amazon. The good news is, whenever there is an update from your cable system, your modem will receive the update, because it is the same equipment most cable companies provide. You should check with your local cable company to be certain it is on their list of compatible equipment. This one IS listed with Comcast cable. I do recommend this type of cable modem over any others that have wireless internet built into them because the wireless internet they provide is normally substandard in comparison to what you can purchase here on Amazon. Any name brand wireless router is good, like Asus, Netgear, Belkin, or Linksys and they all have Ethernet ports on the back. ... show more
Reviewed in the United States on April 23, 2015 by TexasTea
    • Erratic performance.
Review Image by Walt G. Walt G.
This was a purchase from Woot through Amazon and was based on Comcast telling me I had to upgrade to DOCSIS 3. despite working DOCSIS 2 modem. Weekly Speedtest results and daily fluctuations show speeds dropped periodically to 3-4 Mb/s since installing. (The graph is from the times I logged in and shows consistent 30Mb/s for months and then a saw tooth pattern after the modem was installed) I rebooted the router and modem many times, replaced the cables. and disconnected/reconnected the coax with no changes. Today I dug out my old DOCSIS 2 Surfboard and plugged it in. COMCAST/Xfinity went through an activation routine and in 5 minutes I was back to my old speeds. I'm sorry I didn't realize the problem during the shortened warranty period for the refurb unit since it looks like it was faulty since day 1. I'll run the old router for a few days but I think I found the problem. Last several tests are all at 30Mb/s ... show more
Reviewed in the United States on November 2, 2015 by Walt G. Walt G.

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