Features: 1.[Comfortable Breathable] Made of high quality materials, the posture corrector is lightweight, comfortable and breathable. 2.[Ergonomic Design] With ergonomic design, the posture corrector does not lean, and fits the spine well without burden. 3.[Adjustable] The elasticity of this posture corrector can be adjusted without sliding, making the adjustment more convenient. 4.[Wear Resistant] Using sophisticated production technology, the posture corrector is wear resistant and durable. 5.[Long Battery Life] Has excellent performance and long battery life, can be charged for one hour, and be used for 15 days. specification:Item Type: Posture Corrector Material: ABS, Nylon Product Function: Spine Correction, Chest Extension, Improvement of Kyphosis, Prevention of Rickets, Protection of Eyesight Battery Type: Lithium Battery (Shipped with Built in Battery) Battery Model: 802035 Battery Capacity: 400mAh Charge for One Hour: 15 Days Available Indicator Light Description: Blue Light On: Work Instruction Red Light On: Charging Green Light On: Charging is Complete Three Weeks of Continuous Use Effect: Shoulder Expansion and Back Expansion: the Effect in the First Week, Adjustment Period, Should Not Be Too Tight, Let the Spine Adapt First. Stand Up Your Chest and Raise Your Head: the Effect in the Second Week. During the Maintenance Period, Adjust the Tightness Slightly to Let the Spine Get Used to It. Straight Waist and Abdomen: the Effect in the Third Week, a Certain Effect Can Be Seen After Three Weeks of Use Indicator Light Description Blue Light is On, Red Light is On, Green Light is On, Working Indicates That Charging is Complete During Charging PackageList:1 x Posture Corrector 1 xUSB Cable NoteShipped with Built in Battery