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Tau Bike Light Instructions

The Tau is a bright and very, very, (very), lightweight LED bike safety light that is USB rechargeable and has a wide beam to help you be safe and seen.

Download the Tau PDF instruction sheet

Charge the Batteries

Tau comes with a built in rechargeable battery. This can be recharged by connecting to a USB socket with the USB cable provided. The socket is on the rear of the lighting unit, under a small rubber flap. Leave around 70 minutes for a full recharge.

Instructions for use

Press and hold the power button until the light comes on. Release the button, then press again to shimmy through the lighting modes. 

Depending on whether you have the front or rear lights, the cycles are as follows. 

Tau [Front] modes: 

Low > Medium > High > 6Hz flash > 3Hz Flash 

Tau [Rear] modes:  

Low > High > Pulse > 6Hx Flash > 3Hz Flash 

To switch the light off, press and hold the button until the light goes out. 

Fitting to your bike

Tau does not need any special tools to attach to your bike (hooray!). It is provided with rubber loops to attach to your handlebar, seatpost, or seatstay. 

  1. Attach one end of the rubber loop to Tau, making sure it clicks into place. 
  2. Stretch the rubber loop around the bike component and back onto your Tau 
  3. Check it is secured. 
  • Do not shine torch directly into your eyes 
  • Do not submerge. 
  • Do not disassemble or modify this product as it will invalidate your warranty 
  • Recycle batteries responsibly 
  • LED lights are not replaceable 

Wipe down torch body with a damp cloth. To wash the elasticated straps remove from the torch body. Wash at a low temperature. 


Ensure the torch is completely dry. Store in a cool, dry place – but don't leave it too long before you get out and start enjoying the dark again! 

Service and repairs

If this light does not function check the batteries are fully charged. Check there is no water in the torch, dry thoroughly if there is and try again. Check for signs of corrosion caused by batteries leaking or through damp. If an issue can't be corrected using these instructions, contact Alpkit for advice. 


Bulb: 1 x COB LED strip 270° beam 

Power source: 3.7 V 300 mAh Li-polymer 

Cable: Micro USB 

Mode Brightness Beam intensity Beam Distance Run time Water Resistance
Front High 65 lm 25 cd 10 m 4 h
Front Med 30 lm 13 cd 7 m  8.5 h 
Front Low 10 lm 5 cd 4 m 30 h
Front 6 & 3 Hz - 12 h
Rear High  20 lm 6 m  3 h
Rear Low 6 lm 16 h
Rear 6 & 3 Hz - - - 18 h
Pulse  - - - 15 h

Updated: Jul 14, 2017

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