For more sporty outlook of double diamond frame, the Cito E+ Top tube Add-on allow user who want more traditional outlook. There is a storage space with twist knob to switch on/off the box. Using storage bag for easily access to storage items. FEATURES: ? To change the low step through frame to sporty look diamond frame. The storage space inside the tube offer the convenience to the rider for small personal stuff. SPECS: Material: aluminum Color: matte black Weight: 1.5lbs/ 0.7kg Max load: 33lbs/ 5kg