Do you struggle to maintain a mobile phone signal in your home or office? Does your mobile phone line break up during an important phone call? Finally, there is a solution for poor signal strength! Cel-Fi 3G/4G mobile signal boosters are designed to address the challenges faced by businesses and consumers every day when trying to make and receive mobile phone calls in the home and office. Available for O2, EE, Vodafone UK and Three, they boost both the 3G and 4G signal simultaneously.Cel-Fi Smart Signal Boosters are licence exempt under UK law and fully meets the requirements of Ofcom SI 2018/399.