---
product_id: 164528382
title: "Circle Smart Bike Brake Tail Light"
brand: "g keni"
price: "NT$1552"
currency: TWD
in_stock: true
reviews_count: 13
category: "G Keni"
url: https://www.desertcart.tw/products/164528382-circle-smart-bike-brake-tail-light
store_origin: TW
region: Taiwan
---

# 120 lumens ultra bright 50h USB-C rechargeable Smart brake alert Circle Smart Bike Brake Tail Light

**Brand:** g keni
**Price:** NT$1552
**Availability:** ✅ In Stock

## Summary

> 🚴‍♂️ Light up your ride, brake smart, ride safe — never blend into the night again!

## Quick Answers

- **What is this?** Circle Smart Bike Brake Tail Light by g keni
- **How much does it cost?** NT$1552 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.tw](https://www.desertcart.tw/products/164528382-circle-smart-bike-brake-tail-light)

## Best For

- g keni enthusiasts

## Why This Product

- Trusted g keni brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Power That Lasts:** 400mAh battery delivers up to 50 hours runtime with fast USB-C charging and clear battery indicator.
- • **Brake-Savvy Safety:** Instant ultra-bright brake alert mode keeps you visible and protected in traffic.
- • **Built for the Elements:** IPX6 waterproof aluminum housing stands up to rain, dust, and rugged rides without fail.
- • **Luminous Long-Distance:** 120 lumens output with visibility up to 1000m ensures you're seen from afar, day or night.
- • **Adaptive Lighting Modes:** Four versatile light modes plus auto on/off sensor tailor your visibility to any ride.

## Overview

The G Keni Smart Brake Sensing Rear Bike Light combines cutting-edge brake detection technology with ultra-bright 120 lumen COB LEDs, offering up to 1000m visibility. Featuring four customizable light modes and an intelligent auto sensor, it adapts seamlessly to your riding conditions. Its durable IPX6 waterproof aluminum design and USB-C rechargeable 400mAh battery provide up to 50 hours of reliable runtime, making it the ultimate safety upgrade for road, mountain, and commuter cyclists.

## Description

desertcart.com : G Keni Smart Brake Sensing Bike Tail Light, Ultra Bright Rear Bike Light, USB C Rechargeable Waterproof Bike Lights for Night Riding with Auto Sensor for Road & Mountain Bikes : Sports & Outdoors

Review: After four years still my favorite tail light! - Great tail light! I am four years n with this light and I’m ordering more only because I love it! Looks great on the bike and works flawlessly! Easy to turn on while riding. Holds a charge very well! Bright! Tucked away under the seat! Super solid mount. Better than any other bike mounted rail light I have used. Not what it needs to be and no more. Perfect design. Cheers! Buy some while you can!
Review: Took them for a spin... totally a 5 star product. - Added this light to the back of a Propel Endeavor S - it was recommended by an Endeavor Pro owner/rider. It's fancy no doubt.. the modes are well balanced to a ride's needs. Very nice touch to have 4 tiny tiny tiny lights inside the red ring as a battery gauge. The main feature that makes this little guy shine -- the brake sensor -- and it does it very well from what I was told when driving past friendships (bc I can't actually see the back of the board while riding) - Built quality -- it's solid.. very nice.. personally, I think devices like these should have bumpers.. this is the type of tech/gear that inevitably will take inconsistent handling, some abuse while removing to charge - then possibly sits in a basket along other smaller gadgets till it needs to go back on the board/bike.. but ehh - it produces a very nice consistent red light - it performs as describe... and I really enjoy having it on the board while I ride. Hope this helps... #Recommend

## Features

- SMART BRAKE ALERT: This smart bike tail light automatically switches to ultra bright mode for 5 seconds when braking to help alert riders and vehicles behind you. A reliable brake sensing bike light for road bikes, mountain bikes, and daily commuting
- ULTRA BRIGHT VISIBILITY: Featuring high brightness COB LEDs with up to 120 lumens output and visibility up to 1000m, this rear bike light helps improve visibility during night rides and low-light conditions. Ideal for bike lights for night riding and everyday cycling safety
- 4 LIGHT MODES & AUTO SENSOR: Choose from Flash, Breathing, Fast Flash, and Steady On modes to match different riding conditions. Built-in motion and light sensors automatically turn the bike rear light off after inactivity and back on when movement is detected
- USB-C RECHARGEABLE: Built-in 400mAh rechargeable battery delivers up to 50 hours runtime depending on brightness settings. This usb rechargeable bike light features adjustable brightness, fast USB-C charging, and a 4-level battery indicator display
- DURABLE & WATERPROOF: Made with a durable aluminum alloy housing and IPX6 waterproof protection, this waterproof bike light is built for rain, dust, rough roads, and daily use. Perfect for commuter bikes, road cycling, and mountain bike riding

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B07W4PGHK7 |
| Auto Part Position | Rear |
| Best Sellers Rank | #27,900 in Sports & Outdoors ( See Top 100 in Sports & Outdoors ) #32 in Bike Taillights |
| Brand | G Keni |
| Brand Name | G Keni |
| Color | Black |
| Customer Reviews | 4.5 out of 5 stars 2,318 Reviews |
| International Protection Rating | IPX6 |
| Item Dimensions L x W x H | 1.57"L x 1.34"W x 1.34"H |
| Item Weight | 3 ounces |
| Light Output Maximum | 120 lumens |
| Manufacturer | K&K International Co.,LTD |
| Manufacturer Part Number | Q5 |
| Material | Aluminum, Plastic |
| Material Type | Aluminum, Plastic |
| Model Number | Q5 |
| Mounting Type | Seat Mount |
| Number of Items | 1 |
| Number of Pieces | 1 |
| Number of settings | 4 |
| Power Source | Battery Powered |
| UPC | 730964003983 |
| Warranty Description | 1 Year |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** G Keni
- **Color:** Black
- **Item Weight:** 3 ounces
- **Light Output Maximum:** 120 lumens
- **Material:** Aluminum, Plastic
- **Mounting Type:** Seat Mount
- **Number of settings:** 4
- **Power Source:** Battery Powered
- **Product Dimensions:** 1.57"L x 1.34"W x 1.34"H
- **Water Resistance Level:** Waterproof

## Images

![Circle Smart Bike Brake Tail Light - Image 1](https://m.media-amazon.com/images/I/7106EjtMgML.jpg)
![Circle Smart Bike Brake Tail Light - Image 2](https://m.media-amazon.com/images/I/61RXOjOg83L.jpg)
![Circle Smart Bike Brake Tail Light - Image 3](https://m.media-amazon.com/images/I/71gnvUgp77L.jpg)
![Circle Smart Bike Brake Tail Light - Image 4](https://m.media-amazon.com/images/I/61jInCNoJBL.jpg)
![Circle Smart Bike Brake Tail Light - Image 5](https://m.media-amazon.com/images/I/61PQF8Kp59L.jpg)

## Available Options

This product comes in different **Style** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ After four years still my favorite tail light!
*by A***G on April 20, 2025*

Great tail light! I am four years n with this light and I’m ordering more only because I love it! Looks great on the bike and works flawlessly! Easy to turn on while riding. Holds a charge very well! Bright! Tucked away under the seat! Super solid mount. Better than any other bike mounted rail light I have used. Not what it needs to be and no more. Perfect design. Cheers! Buy some while you can!

### ⭐⭐⭐⭐⭐ Took them for a spin... totally a 5 star product.
*by S***T on February 23, 2022*

Added this light to the back of a Propel Endeavor S - it was recommended by an Endeavor Pro owner/rider. It's fancy no doubt.. the modes are well balanced to a ride's needs. Very nice touch to have 4 tiny tiny tiny lights inside the red ring as a battery gauge. The main feature that makes this little guy shine -- the brake sensor -- and it does it very well from what I was told when driving past friendships (bc I can't actually see the back of the board while riding) - Built quality -- it's solid.. very nice.. personally, I think devices like these should have bumpers.. this is the type of tech/gear that inevitably will take inconsistent handling, some abuse while removing to charge - then possibly sits in a basket along other smaller gadgets till it needs to go back on the board/bike.. but ehh - it produces a very nice consistent red light - it performs as describe... and I really enjoy having it on the board while I ride. Hope this helps... #Recommend

### ⭐⭐⭐⭐⭐ Seems Like a Very Good Tail Light
*by R***S on June 21, 2021*

This is a nice bright light, easily visible from a distance in daylight over a reasonable range of angles from the rear. The mount is very good. It is solid and secure and about as high on the bike as anything can be. It is well constructed, with an aluminum body and aluminum screw-in receptacle on the mount. The button is firm with distinct tactile feedback that you have pressed it. The battery strength indicator lights are very small but visible. There are four modes, only two of which I use. The first two have auto-on and off features that I don't trust and flashing patterns I don't like. The third one has a an eye catching strobe that I normally use to be visible to cars and the fourth one is steady on for when someone is riding behind you and the strobe would be distracting. The brake light feature works pretty well, which is also good for when someone is riding behind you. I like it so much I bought a second one for my daughter's bike.

## Frequently Bought Together

- G Keni Smart Bike Tail Light, Brake Sensing Rear Lights, Auto On/Off, Waterproof, USB Rechargeable, Ultra Bright LED Warning Back Bicycle Flashlight, Cycling Safety Accessories
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*Product available on Desertcart Taiwan*
*Store origin: TW*
*Last updated: 2026-08-20*