If you were a fan of the Magicshine’s Seemee 200 but didn’t think 200 lumens were enough, then we have good news for you. The new Magicshine Semee 300 we have here combines all the innovative features of the Semee 200 but adds a second LED to achieve a blinding 300 lumen output. Despite the combination of two focused LEDs, a downward facing OptiTracing LED and a COB LED ring, the Seemee 300 still has an affordable $59.99 retail price. With 300 lumen of output and a variety of flash modes and constant modes to choose from it’s a very bright taillight. Magicshine has also incorporated smart features such as a brake sensor and ambient light sensor which is utilized in the smart output modes. Fans of Magicshine will also be excited to know that the Seemee 300 finally incorporates USB-C to charge the 1600 mAh battery.

The Magicshine Seemee 300 offers an impressive 300 lumen output from two focused LEDs, a downward LED and a COB LED ring.

Retail Price$59.99
Rating9.3 / 10
Measured Weight (in g) 76 (taillight), 11 (seatpost mount), 4 (saddle rail mount)
Likes+ Blindingly bright with 300 lumen output
+ Dual lighting elements offer excellent visibility
+ Smart mode automatically adjusts to environment
Dislikes– Extruded lens has a lip that can collect dirt
– OptiTracing LED can’t be disabled manually
Where to Buy (US)Magicshine
15% OFF coupon code: “TheSweetCyclists”


The Magicshine Seemee 300 taillight comes in compact black cardboard boxes with Magicshine branding and specs printed onto it. Inside the box you’ll find:

  • Seemee 300 taillight
  • USB-C charging cable
  • Seatpost mount
  • Saddle mount + 2x zip ties
  • Instruction manual
  • Warranty card

Magicshine has done a great job eliminating excess packaging or plastic usage by using a folding orange cardboard inner piece to hold the taillight in place and create compartments inside the box.


Magicshine has utilized a miniaturized Garmin quarter turn style mount for the Seemee 300. It’s a two piece design with a protruding tab built into the housing of the Seemee 300 and a separate rubber and plastic seatpost mount. As with other Garmin mounts, you simply align the tabs and rotate the taillight to lock it in place. The seatpost mount has an angled rubber backing with multiple cutouts to support different seatpost shapes and a thick rubber strap. An additional plastic saddle rail mount is included which allows the taillight to tuck underneath the saddle. Note, the mount size of the Seemee 300 appears to be identical to the other Seemee taillights like the Seemee 150 and Seemee 200 so the mounts are interchangeable between models.


The Magicshine Seemee 300 combines the innovative features of the Seemee 200 but adds even more output and a modern design. The taillight uses what we’d describe as an open lens design with the two focused LEDs inset into the black covering. An extruded transparent ring wraps around the edge of the housing with COB LEDs behind it. Underneath the light is the OptiTracing LED which is a downward facing LED that illuminates the ground beneath you with additional visibility. The LEDs all use red filaments instead of a red lens which gives the taillight a clear or Altezza style appearance when the lights are off. It’s a sleek design that gives the Seemee 300 a modern appearance and helps it blend it when it’s not being used. With all the LEDs on the taillight this is a fairly large taillight with a thick rectangular form factor. The main housing on the taillight appears to be metal with Magicshine branding on one side and Seemee 300 printed on the other side.

Magicshine Seemee 300 Smart Bike Taillight LED Review - Power Button
The taillight has a single rubber button that is also back illuminated to indicate the battery level or if the brake sensor is active.

Fans of Magicshine will be happy to see that the Seemee 300 has a modern USB-C charging port. This does not support on-the-go charging but has a thick rubber cover that’s easy to put on and take off. The light uses a familiar single button interface with an illuminated rubber button on top of the light. A short press while the light is off turns the backlight to green, red or flashing red to indicate the battery status. It’s a convenient feature that provides a three-level status and lets you check the battery before you start riding. A long press turns the light on while a single press cycles through the one-level menu. Additionally you can do a long hold with the taillight off to toggle the brake sensor on or off. As with other brake-sensing taillights, we’d recommend disabling the feature for more consistent and long runtimes.

Magicshine Seemee 300 Smart Bike Taillight LED Review - OptiTracing LED
One of the unique features of the taillight is the downward facing OptiTracing LED that automatically turns on in low-light conditions.

The downward OptiTracing LED is one of the coolest features of the Seemee 300 and lights up the road beneath you. As with the Seemee 200 there is no manual control for this LED, it is automatically enabled in low-light conditions. The LED pattern is always the opposite of the main LED mode, i.e. it flashes when main LEDs are in constant mode and flashes when main LEDs are in a flash mode. We would have appreciated a full disable option for the LED as it reduces the runtimes substantially at night. Otherwise, the downward LED does an excellent job of illuminating the area underneath your bike for additional safety while riding.


Magicshine has kept the output modes of the Seemee 300 simple with only five modes to choose from. Effectively there are actually ten output modes as the taillight has day and night version for each mode. The OptiTracing LED is only active at night and for most modes has the same lumen output as the main LED. Note, the OptiTracing LED is always illuminated in the opposite pattern as the main LED and cannot be manually controlled. There are two constant modes: low (20 lumen / 40 – 60 hr runtime) and high (100 lumen / 6-8 hr runtime). Additionally, there are two standard flash modes: a standard on-off flash (100 lumen / 7-45 hr runtime) and a lower-powered eco flash (20 lumen / 50-200 hr runtime). Finally there is a smart mode option which automatically switches between a day-time flash (300 lumen / 35 hr runtime) and a night time flash (100 lumen / 6 hr runtime).

Magicshine Seemee 300 Smart Bike Taillight LED Review - LED Elements
With the Seemee 300 there are two focused LEDs, a COB LED ring and a downward facing OptiTracing LED.

We’d highly recommend the smart mode as it’s highly visible during the day and less jarring at nighttime. The internal ambient light sensor lets it automatically switch modes so you can focus on riding and let the taillight pick the optimal mode. With all the modes there is also an optional brake sensing feature which switches the taillight to a full brightness constant mode for a few seconds when braking is detected. Magicshine has done a good job tuning the sensor sensitivity to minimize false-positives and the change in output mode does a good job alerting people behind you. We’d still recommend disabling the brake sensor feature if you ride longer distances as it can result in inconsistent runtimes or lower runtimes when doing longer rides.


Overall, we found the Magicshine Seemee 300 to be an impressively bright and well designed taillight. Magicshine has incorporated the same downward OptiTracing LED from the Seemee 200 but added a second LED and modernized the design and features. We’re happy to see the USB-C charging port and extended COB LED stripe which improves side visibility. The brake sensor is also well calibrated while the ambient light sensor lets the taillight automatically switch between appropriate output modes. It’s an impressive taillight with a lot of output, the only potential flaws with it is that the open-lens design collects dirt and that you can not disable the OptiTracing LED. That said, if you’re looking for a bright taillight with long-distance visibility the Seemee 300 is an excellent option.

Disclaimer: The product for this review was provided by Magicshine. The views expressed on this website are solely those of the authors and are here to help people make an informed choice before a purchase. The authors or the blog itself does not get any monetary compensation from the product manufacturer or third-party websites/vendor links that are posted here.

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