Specification: Shell material: aluminum alloy Waterproof Grade: IPX4 Charging current: 5V 280mA Mounting method: saddle/seat tube Battery capacity: 350mAh Product size: 31.3*31.3*24.2mm Mode switch (manual/automatic): double-click to switch in working mode (boot) Weight: about 75g Packing size: 13*7.2*3cm Features: Fresnel perspective lampshade, high brightness and soft use of light. 6 Lighting Modes Always on/breathing flashing/slow flashing/fast flashing/rhythm flashing/eco flashing (energy saving); IPX4 Waterproof Design Proper to any abusive environment Power Reminder Function Reminding the power situation in time, so as to plan the usage according to the remaining power; The 2 Basic Modes Can Be Switched Freely. In manual mode/intelligent mode, the intelligent mode can automatically sleep or wake up according to the environment and operation, saving power; Smart Braking Sensor Light Built-in acceleration sensor, intelligent induction braking, highlight reminder, and filter false alarms in bumpy situations; 2 Installation Methods Equipped with two mounting brackets, which can be installed at the saddle/seat post according to usage habits; Small and portable in size, no burden on bicycles