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Open Box: Cel-Fi GO X

by Cel-Fi

Single carrier signal booster with industry-leading 100dB gain.
Open Box: Cel-Fi GO X has a rating of 4.9 stars based on 93 reviews.

Retail price: $1,099.99 You save: $200.00

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Product Description

Please note: This is an open-box part, and may have minor surface blemishes or scratches that don't impact performance.
The product will contain all original parts and accessories, and can be returned within 90 days from receipt of the product for a full refund (not including any expedited shipping costs).


The Cel-Fi GO X is an in-building signal booster system that utilizes Nextivity’s Cel-Fi Smart Signal Booster technology to significantly boost voice and data coverage.

Also available in a high-performance MIMO configuration.

The GO X is different from the majority of other boosters we sell in 3 ways:

  • The Go X is a single-carrier device and will amplify signal for just one of the following carriers at a time: AT&T, Verizon, or T-Mobile.
  • The GO X offers up to 100 dB gain. Unlike most of our other broadband, multi-carrier devices, the Cel-Fi Go X is not restricted to 70 dB gain by the FCC.
  • The Go X is NEMA 4 weather-resistant and can be installed outdoors.
  • Important note for Verizon customers: this device supports Verizon’s 4G LTE service only. It does not support 3G or 2G Verizon service. Most newer devices (basically all phones released since 2014) support “voice over LTE,” however if you have a very old phone or don’t have a 4G LTE signal, you can’t use the GO X. (The GO X does support AT&T and T-Mobile 3G service).

The additional 30 dB gain makes the Cel-Fi Go X the best solution for buildings where outdoor coverage is weak (less than 3 bars or -80 dBm RSRP).

The Go X can be used in all kinds of applications, including:

  • Homes
  • Businesses
  • Retails
  • Hospitals
  • Warehouses
  • Industrial facilities
  • Outdoor applications

Please note that the Cel-Fi GO X can only boost signal for one network at a time. If you have users on multiple networks in your building, you may need a multi-carrier booster or multiple GO X devices.

The Cel-Fi GO X can boost the following bands:

  • AT&T bands: B2, B4, B5, B12
  • Verizon bands: B2, B4, B5, B13
  • T-Mobile bands: B2, B4, B5, B12

Cel-Fi WAVE Mobile App

The GO X can be easily optimized and monitored by the Cel-Fi WAVE application for iOS and Android devices. Cel-Fi's mobile app allows you to connect to the device over Bluetooth and see detailed diagnostic information, including measures of signal strength (RSRP), gain, and signal quality (SINR).

5G DSS Upgrade

With various forms of 5G rolling out across carriers, 5G support is increasingly important!

The Cel-Fi GO X is the only consumer-grade signal booster capable of relaying 5G-DSS at 100 dB of gain.

Dynamic Spectrum Sharing (DSS) is used by some carriers to transmit 4G LTE and 5G in a single “hybrid” channel. 5G DSS Support on the GO X is enabled by a software update. Once updated, the GO X is capable of automatically connecting to existing 5G DSS bands.

Coverage Area

As with all signal booster kits, the coverage area of the Cel-Fi unit depends on two factors:

  • The number of indoor antennas you pair it with
  • The signal strength at the location where the outdoor "donor" antenna is installed.

Up to 15,000 sq ft coverage is possible in an open area by utilizing 4 indoor antennas. In a typical home or office environment, up to around 5,000 sq ft coverage is possible from a kit with four antennas. Read more below under "How many antennas do I need?"

Picking The Right Kit

Need help?

We have our own guide to setting up the Cel-Fi GO X available here. It discusses in depth some of the most common troubleshooting issues we've seen customers face.

We've put together standard kits that you can purchase to install the Cel-Fi Go X, but we can also customize a kit for your building. Simply contact us and one of our signal experts will put together a custom kit specifically for your building.

Looking for the fastest data speeds?

If you're looking for a signal booster to provide the fastest possible data speeds, check out our Cel-Fi Go X MIMO Kit

Using a MIMO system can increase your data speeds by up to 30%!

By using two amplifiers in parallel, the Cel-Fi GO X MIMO Kit is the first consumer-grade signal booster system that can boost MIMO signals.

The result is maximum wireless data speeds, all the time!

Which outdoor antenna should I purchase?

We offer two different outdoor antennas with the Go X: a Standard Log periodic Antenna, and a Grid Parabolic Antenna. Both antennas come with mounting equipment to attach to a 1 to 2 inch diameter pole

Standard Log Periodic Antenna

The Wideband Log Periodic Outdoor Antenna is a powerful antenna that offers up to 10 dBi of gain across all 4G LTE and 5G frequencies. It needs to be set up pointing in the direction of the cell tower, and because it is directional it will only pick up signal in that direction. 

Griddy: The Grid Parabolic Antenna

Griddy: The Grid Parabolic Antenna is an ultra-wideband, ultra directional parabolic grid antenna. Griddy adds up to 26 dBi of gain across all 4G LTE and 5G frequencies.

If you have line of sight to your cell tower, Griddy can help make signals considerably stronger and clearer

We can't stress this enough - Griddy has a very, very narrow beam width and only “sees” a very narrow horizontal and vertical aperture. This means it will take some additional careful aiming to get dialed in. Even a 1-2 degree variance can make a huge difference.

How many indoor antennas do I need?

In general, the more antennas you have, the larger the coverage area of the system. Signal passes through cables much more easily than through walls and even through the air, so adding more antennas helps expand the coverage of your booster.

As a rule of thumb, we recommend installing one antenna for every 750 sq ft to 1000 sq ft of space in a typical home or office environment that is subdivided into smaller spaces. If the environment is more open, such as in a warehouse or open office floor, you can install one antenna for every 1,500 to 2,000 sq ft.

Two types of indoor antenna?

We've packaged the Cel-Fi Go X with two different kinds of antennas in each kit: a Dome Antenna and a Panel Antenna.

Dome Antennas spread signal in all directions. To install a dome antenna, you need access to the back side of the ceiling (e.g. a loft or crawl space) to run cable.

Panel Antennas direct signal in the direction they are pointing. They can be installed on a wall.

We include both antennas in our kits - pick which one you want to use and discard the other. For example, if you order a kit with 3 indoor antennas, you'll receive 6 total antennas - 3 domes and 3 panels - but you'll only be able to connect 3 of them to your GO X.

Dome antenna radiation pattern:

Dome Antenna Radiation Pattern

Panel antenna radiation pattern:

Panel Antenna Radiation Pattern

Kit Contents

Cel-Fi Go X Amplifier-Only

  • Cel-Fi Go X Amplifier
  • Power Supply (15 Volt, 1.5 Amp)
  • Quick Start Guide

Cel-Fi Go X Kits

If you order a kit with a Grid Parabolic outdoor antenna, we also include:

If you order a kit with more than 1 indoor antenna, we also include:


Cel-Fi warranties the GO X for 2 years, and Waveform warranties all of our antennas and RF components for 3 years.

Read more about Cel-Fi and Waveform's warranty policies here.


The coverage area you can expect from any signal booster kit depends on the signal strength outside the building.

Outdoor Signal Estimated coverage area
Strong outdoor signal (5 bars) up to 15,000 sq. ft. coverage
Medium outdoor signal (3-4 bars) up to 10,000 sq. ft. coverage
Weak outdoor signal (1-2 bars) up to 5,000 sq. ft. coverage

Product video


Coverage 5000 sq ft (1 coverage with weak signal)
10000 sq ft (2 coverage with medium signal)
15000 sq ft (3 coverage with strong signal)

Customer reviews

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Our signal experts have helped design and install kits in buildings of over 200,000 sq ft. Let us help you find the right product.

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