These new style travel cases are made of two ultra strong materials. The sidewalls are made of high strength aluminum and the corners are made of impact-resistant plastic parts. The components are vary durable and water-proof bonded by a specially developed riveting technology! Volume of each case is app. 37 L. To secure your luggage an additional lock kit 60112023050 (includes 4 locks for both cases) is available. To secure side cases and top case, please order the lock kit 60112023150 (includes 6 locks). Optional inside pockets available: 60112024070.