Download the package form Robo3t or using wget
wget https://download.robomongo.org/1.2.1/linux/robo3t-1.2.1-linux-x86_64-3e50a65.tar.gz
tar -xvzf robo3t-1.2.1-linux-x86_64-3e50a65.tar.gz
wget
wget https://download.robomongo.org/1.2.1/linux/robo3t-1.2.1-linux-x86_64-3e50a65.tar.gz
tar -xvzf robo3t-1.2.1-linux-x86_64-3e50a65.tar.gz