The Klarus X5 is one of the first lights on the market to feature a AAAA (that is four As) and still have a whole lot of output.  The X5 achieves an incredible 76 lumens in its very, very small form factor by using a special circuit to power the CREE XP-E R2 LED.  Even more impressive, the four output levels are digitally regulated and have no PWM that can cause flickering.

Features:

• Durable, compact and reliable. Designed for every day carry
  
• The SMALLEST and Brightest AAAA flashlight in the world
  
• Digitally regulated output - maintains constant brightness, no PWM
• Max output: 76 Lumens.
  
• Max run time: 26 hours
  
• Reverse polarity protection

Specification:

• Emitter: Cree XP-E R2 LED with a lifespan of 50,000 hours
• Four outputs:
  
• 25 lumens（2.2 hours）
• 2 lumens（26 hours)
  
• 76lumens（40 minutes）
• Strobe (76 lumens, 1.2 hrs)
• Battery: Single AAAA (Alkaline, Ni-MH, Lithium)
  
• Switch: Twist switch, Adjust output by rotating the flashlight head
  
• Lens: Toughened ultra-clear glass
  
• Material：Stainless steel
  
• Dimensions：65.6mm (Length) x 9.2mm (Body) x 10.3mm(Head)
  
• Net weight: 11g (Excluding battery) 9. Waterproof to IPX-8 standard