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Serfas Thunderbolt USB Rear Bike Light


    Serfas Thunderbolt USB Rear Bike Light

    The Serfas Thunderbolt USB rechargeable rear bike light lets you alert others to your presence, thanks to its bright strip of micro LEDs. See details

    • $45.00

    Item # 852297

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    The Serfas Thunderbolt USB rechargeable rear bike light lets you alert others to your presence, thanks to its bright strip of micro LEDs.

    Product size and color

    The Serfas Thunderbolt USB rechargeable rear bike light lets you alert others to your presence, thanks to its bright strip of micro LEDs.

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    The Serfas Thunderbolt USB rechargeable rear bike light lets you alert others to your presence, thanks to its bright strip of micro LEDs.

    • The strip of 30 red micro-LED bulbs puts out up to 35 lumens of light; strip design puts out a nondirectional flood of light for wide coverage area
    • Water-resistant, flexible and finish-friendly silicone body and adjustable straps stretch around your bike's frame for easy, tool-free mounting and removal
    • 4 modes (with run times): high beam/constant (1.75 hrs.), low beam/constant (7 hrs.), high flash (3 hrs.), low flash (9.5 hrs.)
    • USB rechargeable design of the Serfas Thunderbolt rear bike light lets you recharge the light via a USB port; recharges in 2 hrs.


    Item 852297

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    Serfas Thunderbolt USB Rear Bike Light Specs
    Best use
    30 micro
    Multiple locations
    2 hours
    Lithium ion
    1.75 hours
    7 hours
    9.5 hours
    50 grams
    Bulb type
    Number of bulbs
    Taillight mounting
    Charge time
    Integrated battery
    Battery life on high
    Battery life on low
    Battery life flashing

    Serfas Thunderbolt USB Rear Bike Light

    Loading Ratings & Reviews...

    Serfas Thunderbolt USB Rear Bike Lightis rated4.3889out of5by18.
    Rated4out of5byfromImpressedI did quite a bit of research online about the best rear safety light and narrowed it down to the Cygolite Hotshot and the Serfas Thunderbolt. The Thunderbolt is $10 more than the Hotshot and I wasn't sure if it was worth it b/c they both get excellent reviews. Since I couldn't decide which one to buy, I bought both and figured I would pick a winner and return the loser or possibly keep both since they're a little different. To test them out, I placed both on a fence during the afternoon in bright, direct sunlight and turned them on their brightest, flashing setting. I backed about 25 feet away and it was immediately evident that the Thunderbolt is WAY brighter and much more visible. It's not even a fair comparison. I was very surprised at how the Hotshot performed, considering the reviews I've read. I'm keeping the Thunderbolt and returning the Hotshot
    Date published: 2014-02-20
    Rated4out of5byfromVery bright light.I am very impressed by the brightness of the light. It is bright even during the day. I was surprised when it transitioned from being very bright to being out of charge over a couple of seconds. I would prefer if it gave me a warning that it was running out of charge.
    Date published: 2014-01-22
    Rated4out of5byfromBright!Overall, this light is great. It is really bright (the package claims you can see it a mile away, but i have not tested this). I usually run it on the lower setting since its plenty bright enough and to save the battery. It does seem the downside to all this power is that the battery doesn't last super long on high or really even on low for that matter. I can get about 6 hours on low and about 2 on high. However, since its rechargeable this is not really an issue, i just make sure to regularly charge it. The charge cable over port is a bit fiddly but otherwise easily accessible.
    Date published: 2014-01-09
    Rated2out of5byfromBright but Very Short Battery LifeIt's odd that others say the battery life is a pro. My average rides are 3+ hours and the light never lasts the whole ride. I like to use the light during the day as well and put it on the bright, blink setting and it's dead in 1.75 hours. Keep this in mind; the battery life is poor for those that do long rides. Secondly, the on/off switch is recessed in such a way that if you're wearing gloves, it's really difficult to turn on or off. For the price, I'm really dissatisfied with this product. Instead of replacing my old light, I now have to use both just to get through a ride.
    Date published: 2013-12-24
    Rated5out of5byfromGreat lightI have used this light a few times now and must admit that it is very nice that I can be seen from behind. Trust me, you can't miss this light.
    Date published: 2013-11-02
    Rated5out of5byfromBest Light EverWith five bikes I keep trying rear safety lights as most of the previous purchases have not lived up to their expectations. This one is the exception. I have it mounted on the rear downstay of my Cannondale EVO Super Six and it is a blazing light. Generally I use the blinking feature, set on low rather than the high intensity. Highly recommended.
    Date published: 2013-10-30
    Rated5out of5byfromSuper Bright bike lightVery bright rear light for bicycles, I feel confident that everyone can see me when I have this light installed on my bike. Also very quick to install or remove
    Date published: 2013-10-25
    Rated3out of5byfromgood intensity lightI like the light from an overall intensity/brightness standpoint, however the switch seems to be faulty and I have difficulty turning it on or off. I use it in the flash mode, and it so far has decent life.
    Date published: 2013-10-17

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