The Lupine C14 taillight is Lupine’s first rear light to feature a magnetic mount for quick and easy installation or removal. Designed to sit between the saddle seatrails, the C14 Mag is a compact taillight that features quite a few smart features. Lupine offers two versions, the $150 magnetic saddle rail mount version we have in this review and a $125 StVZO version that mounts to seat posts as well as e-bike variations. With the C14 Mag version we have in this review, the taillight is rated for up to 45 lumen output and 22 hour runtime. As with all Lupine products, the C14 Mag uses an all-aluminum construction and a fully serviceable construction that allows you to easily replace the Li-ion battery. To make the C14 Mag “smart” Lupine has also incorporated a brake and ambient light sensor to allow the taillight with optional brake sensing mode and auto-standby modes.

The Lupine C14 Mag combines a magnetic saddle rail mount with an aluminum housing and a serviceable design and replaceable battery.

Rating 8.0 / 10
Retail Price $150
Measured Weight (in g) 50 (taillight), 16 (mount)
Likes+ Sleek magnetic saddle rail mount that tucks underneath the saddle
+ Fully serviceable design including a replaceable battery
+ Compact form factor and bright LEDs
Dislikes– Premium price
– Clumsy user interface with long holds and counting flashes to change mode
– Proprietary magnetic charging cable instead of USB-C
Where to Buy (US)Lupine


The Lupine C14 Mag comes in a compact square cardboard box with branding printed directly on it. Inside the box you’ll find:

  • C14 Mag taillight
  • Aluminum saddle rail mount
  • Multiple length bolts to accommodate different saddle rails
  • Magnetic charging cable to USB-A
  • Allen key (for mount bolts) + screw driver (for taking apart the light)
  • Instruction manual

With the aluminum construction the C14 Mag feels and looks expensive right out of the box.


One of the main features of the Lupine C14 Mag is the magnetic seatrail mount. This combines a seatpost bracket and slot design with an integrated magnet to hold the taillight securely in place rather than a quick release button like the Topeak Duo Fixer mounting system. Unlike most saddle rail mounts, the C14 Mag uses an aluminum design with two bolts that clamp the saddle rail from the top and bottom. Included with the light are two longer screws to accommodate taller carbon rails. The mount requires a minimum of 21mm between the saddle rails and seat and works with nearly any dual rail design that is approximately 35mm apart. Additionally, the bracket requires 13 mm of flat saddle rail to mount onto. The magnets are quite strong which means it requires a fair amount of force to pull the taillight off the mount. It’s highly secure and can even handle gravel riding. The big downside of the saddle rail design is that it prevents you from using strap-style saddle bags.

Lupine C14 Mag StVZO Bike Taillight Review - Mount
What’s unique about the C14 Mag is the saddle rail mounting system which uses an aluminum bracket with an integrated magnet.


The C14 Mag is one of Lupine’s latest taillights and combines a compact form factor with a slick saddle rail mounting to tuck the taillight under the saddle. Lupine is a brand known for their high quality products and German precision which is why they haven’t cut any corners with the C14 Mag. Unlike most plastic products on the market, the C14 Mag and mount utilize CNC-milled aluminum and have a fully serviceable design to ensure they outlast your bike. That means the C14 Mag is one of the few taillights on the markets that allow you to replace the Li-ion battery once the battery has reached its end of life. The combination of the aluminum construction and replaceable battery help justify the premium retail price of the C14 Mag and ensure the light can be used for years to come.

In terms of dimensions, the Lupine C14 Mag is about the size of a lighter with a compact rectangular profile. The rear of the body has an extruded red lens that allows the taillight to achieve an impressive 240 degree visibility. There are multiple COB LED stripes integrated into the lens which creates a unique illumination pattern. On the top of the taillight is a round metal plug which is used in conjunction with the provided magnetic charging cable. It’s similar to the charger design of the Lazer Universal helmet taillight and eliminates the need for weather proofing rubber port covers or USB ports. Although this feature helps the C14 Mag achieve an impressive IP68 rating, which means it can be submerged in water, it means you have to use the provided proprietary charging cable instead of ubiquitous USB cables.

Lupine C14 Mag StVZO Bike Taillight Review - Lens
The C14 has a sleek rectangular profile with a center COB LED strip and six separate elements surrounding it.

A magnet has been embedded into the front of the taillight housing which allows the taillight to sit securely against the matching magnet in the saddle mount. The magnets are quite strong which means the taillight stays securely in place and it requires a good amount of force to remove the taillight from the mount. On the underside of the C14 Mag you’ll find the single button user interface which is backlit to indicate the battery status. There are four battery levels from green to blinking red which make it easier to gauge how much battery is left before starting a ride. An ambient light sensor has also been embedded into the bottom of the housing to help gauge the amount of ambient light around the bike.

One of the common stereotypes of German products is that they are often over-engineered and this holds true with the Lupine C14 Mag’s user interface. By default, a double press of the button turns the light on with all other actions including mode changing accessible only through the configuration option. Lupine knows people don’t read manuals and has printed a cheat sheet for the configuration menu directly onto the taillight. Instead of using an app, the C14 has 8 different options that are accessed by holding the power button for ~8 seconds and then counting the specified number of flashes to toggle each setting. This is very similar to the Lupine Rotlicht we previously reviewed and something we’d describe as clever yet annoying.

The eight options are enabling or disabling: double press to turn the light on, light sensor and brake sensor functionality. These are useful options as you can extend the runtime by using the light sensor and disabling the brake sensor. Changing the output mode of the taillight has also been incorporated into the configuration menu along with a factory reset. What this means is that even changing between the four available modes requires counting 4 to 7 flashes and releasing the power button which is tedious. We wish Lupine would have allowed a single button press to cycle through modes and hidden the less commonly used options in the configuration menu instead. We would have also liked to see a “smart output mode” like the Magicshine Seemee taillights which automatically switches between daytime flash and nighttime pulse instead of the light sensor mode which simply shuts the light off during the day.


Lupine has incorporated four output modes on the C14 Mag taillight. There are two constant modes: 0.2W low mode and a 0.5W high mode. There are also two flashing modes: a standard flash mode and a more friendly pulse mode. The flash mode is better suited for daytime riding with a high visibility on and off pattern while the pulse gradually ramps upward and downward. Lupine doesn’t publish the lumen output and runtime per mode, but rates the taillight at 45 lumen output and up to 22 hour runtime for the high efficiency flash modes. The optional brake mode switches the output of the current mode to a brighter constant mode for a few seconds to attract attention.

Lupine C14 Mag StVZO Bike Taillight Review
As with other Lupine lights, the C14 Mag has a cheat sheet printed onto the rear which shows the configuration options.

While the 45 lumen output may not sound impressive, especially compared to 400 lumen taillights like the Moon Sports Helix Sense 450, it looks bright and has 240 degree visibility. The lighting element design is interesting with multiple horizontal strips of COB LEDs that look modern and provide a uniform illumination pattern. The taillight is visible during daytime but really excels in lower visibility conditions or foggy days as the compact form factor tucks underneath the saddle. Even though the C14 doesn’t have any sensitivity settings for the brake sensor, like the Lupine Rotlicht, it’s well calibrated and has minimal false positives. It’s a nice feature but one that we’re still on the fence about and recommend disabling to achieve longer runtime.


Overall, we found the Lupine C14 Mag to be compact and sleek taillight. The magnetic mount tucks cleanly under the saddle and has a wide rectangular profile that looks modern and sleek. Lupine’s attention to detail and build quality is well represented with the all aluminum construction and fully serviceable design of the taillight. We found the magnetic mount to be strong and clever as it makes it quick and easy to remove or install the taillight. The main thing we disliked about the Lupine C14 Mag is the fact that the mount prevents you from using saddlebags and the non-intuitive mode change user interface. Even simple light mode changes require checking the cheat sheet printed on the back of the taillight and counting the specified number of flashes. That said, if you’re looking for a slim taillight that’s designed with robustness and serviceability in mind the Lupine C14 Mag is a good choice.

Disclaimer: The product for this review was provided by Lupine. 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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