New bicycle tail light with smart brake sensing, vibration detection, and automatic on/off in 7 colors. This product is sold on Amazon for 3,599 yen. I will sell it at a lower price. 【Vibration Intelligent Sensing & Smart Brake Warning｜The Core of Safe Riding】 Built-in high-precision G-sensor, when decelerating or braking while riding, it instantly switches to the highest brightness red flashing. It reliably alerts vehicles behind you, preventing rear-end collisions at night or on downhill slopes. **⚠️Important:** The brake sensing function only works in "Smart Vibration Sensing Mode." It does not work in manual modes such as constant-on, so please be careful (mode can be switched by double-clicking the button). 【7-Color LED x 4 Modes｜Customize to Color Your Bike】 In addition to the general red color, you can switch to a total of 7 colors: blue, green, purple, cyan, yellow, and white. Equipped with 4 modes such as "Constant On," "Flowing Flash," and "7-Color Cycle," you can coordinate with your mood of the day and frame color. While ensuring visibility, it stylishly enhances your night rides. 【Automatic Off & Automatic Power Off｜Effortless Energy-Saving Design】 In smart mode, it automatically turns off (standby) after being stationary for more than 30 seconds. It automatically turns on again when vibration is detected. Furthermore, if stationary for more than 30 minutes after parking, the power is completely turned off, preventing unnecessary battery consumption. *Continuous use for a maximum of approximately 15 hours is possible (varies depending on the mode used). 【USB-C Fast Charging & Battery Level Indicator｜Peace of Mind for Long Distances】 Adopts the versatile USB Type-C port, fully charged in about 2 hours. Equipped with a large-capacity 430mAh battery. You can check the battery level in real-time with the 4-stage LED indicator on the side, eliminating the anxiety of sudden battery drain during commuting, school, or long rides. 【Compatible with Both Saddle/Seatpost & IPX5 Waterproof】 Two types of mounts are included: "for saddle rails" and "for seatposts." Easy to install without tools, and compatible with a wide range of vehicles such as road bikes, cross bikes, and MTBs. IPX5 water-resistant specification, so you can rest assured even in sudden rain or splashes. *Note: It is not completely waterproof, so avoid submersion. It may not fit some special aero-shaped (extremely flat) seatposts.