Cel-Fi by Nextivity DUO+ Smart Signal Booster, Refurbished

IN STOCK. Ships same or next business day.
In Stock: Ships same or next business day
(NOTE: is not eligible for promo coupons or discounts.)
  • Coverage between 5,000 - 13,000 sq. ft.
  • PLUG & PLAY: If you can use an electrical outlet, you can easily install this kit
  • Boosts In-building 3G/4G/LTE Signal
  • Works for all phones on T-Mobile & Verizon
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Cel-Fi by Nextivity DUO+ Smart Signal Booster, Refurbished

Cel-fi DUO+ Signal Booster Details

The Cel-Fi DUO+ Smart Signal Booster for Verizon and T-Mobile (Certified Refurbished) is part of the next generation of intelligent signal boosters. All Cel-Fi products are designed and developed using the most advanced radio frequency and signal processing technology.

It greatly enhances 4G, LTE, and 3G cell service for all your wireless devices (smartphones, notebooks, hotspots, etc.) on Verizon and T-Mobile for any home or office up to 13,000 sq ft.

The Cel-Fi DUO+ has several advantages over traditional signal boosters:

  • Plug and play setup: just plug in the Network and Coverage units and get better signal.
  • Monitor performance with the Cel-Fi WAVE app.
  • Extreme power good for everything from apartments to large homes.

Unlike multi-carrier signal boosters with a limit of +70 dB, Cel-Fi’s single-carrier solution can boost signal up to +100 dB. That’s a difference of +30 dB or up to 1000x more power compared to multi-carrier boosters.

Eliminate dropped calls, slow data, and poor Verizon and T-Mobile signal from your life with a Cel-Fi PRO Smart signal booster.

For AT&T coverage, check out the Cel-Fi PRO.

All certified refurbished products have been reviewed and recertified by the manufacturer. Same great performance, much lower price.

  • Boosts 4G LTE for any home or office covering up to 15,000 sq. ft
  • Works for all phones & cellular devices, Verizon or T-Mobile only.
  • Complete kit: all parts included, easy install.
  • No monthly fees, no need to be connected to wifi, it just works.
  • Industry-leading design & performance by Nextivity Cel-Fi.

Cel-Fi Wave App

Cel-Fi WAVE is the software application and cloud-based portal solution used for registering, setting-up, optimizing, remotely monitoring, and updating the Cel-Fi hardware. Available on iOS, Android, Tencent, PC, and Mac devices.

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Who is this for?

The Cel-Fi DUO+ Smart cell phone signal booster is for:

Those who have large apartments.

Those in rural areas who struggle with Verizon and T-Mobile signal.

Anyone with a large home, office, warehouse, or other building who wants better, more reliable Verizon and T-Mobile signal.

Compatible With Verizon & T-Mobile

The Nextivity Cel-Fi Duo+ Smart Signal Booster amplifies talk & text, 3G, and 4G LTE for Verizon or T-Mobile.

Compatible Carriers (4G LTE & 3G): T-Mobile

Kit Includes:

Cel-Fi Duo+ Network Unit Amplifier
Cel-Fi Duo+ Coverage Unit Amplifier
Power Supplies
Mounting Brackets
Screws & Drywall Anchors

Tech Specs

Nextivity Cel-Fi Duo+ Smart Signal Booster
Model D32-2/4/12
Frequency Band 12, 700 MHz; Band 4/66, 1700/2100 MHz (AWS); Band 2,1900 MHz
Max Gain 100 decibels (dB)
Power 100-240 V AC, 47-63 Hz, 12 V DC
Dimensions Network Unit 6.24 x 5.75 x 2.32 in / 15.85 x 14.6 x 5.9 cm
Dimensions Coverage Unit 6.24 x 5.75 x 2.32 in / 15.85 x 14.6 x 5.9 cm
Weight Network Unit 1.23 lbs / 0.56 kgs
Weight Coverage Unit 0.86 lbs / 0.39 kgs


This is a CONSUMER device. BEFORE USE, you MUST REGISTER THIS DEVICE with your wireless provider and have your provider's consent. Most wireless providers consent to the use of signal boosters. Some providers may not consent to the use of this device on their network. If you are unsure, contact your provider. You MUST operate this device with approved antennas and cables as specified by the manufacturer. Antennas MUST be installed at least 20 cm (8 inches) from any person. You MUST cease operating this device immediately if requested by FCC or a licensed wireless service provider.


Installing the Cel-Fi DUO+ is remarkably easy.

  1. Set up the Network Unit near a window with the strongest Verizon and T-Mobile signal and plug it into an outlet.
  2. Set up the Coverage Unit where desired, preferably as far away from the Network Unit as possible to avoid oscillation. Plug it into an outlet.
  3. Download the Cel-Fi WAVE app to register and set up your booster.
  4. Enjoy your boosted signal!

The Nextivity Cel-Fi Duo+ is easy to install. Everything is included in the kit. Our trained product specialists can also assist if you have any questions. Call 1-800-470-6777 or email sales@signalboosters.com.

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