A containment device that opens to form a mat or work surface that has a raised lip or edge structure that contains items on the mat or work surface. The containment device closes or converts from the mat configuration to create a sealed bag or sealed flexible container for holding the items inside, where the seal is formed by the lip or edge structure. In some embodiments, the containment device may include a cinch cord that can be used to change from the open mat configuration into the closed bag configuration. In such embodiments, the cinch cord may include a cord lock that may be adjustably deployed to clamp the cinch cord and the lip in a position that maintains the convertible luggage device in a closed bag configuration.