These new style alu cases are made of two ultra strong materials. Sidewalls are made of highstrength aluminium the corners are made of impact-resistant plastic parts. The components are durable and water-proof bonded by a special developed riveting technology! Volume of each case is app. 37 L. To secure your luggage an additional lock kit 60112023250 (includes 4 locks for both cases) or 60112023150 (includes 6 locks for sidecases plus top case) is available.