The TK22 V2 has four modes of brightness, powered by either one 18650 or 21700 (batteries sold separately). To switch between them, click the silver button. The tailcap controls power, and allows for momentary-on when you don't fully press it in. The TK22 V2's body is machined from aluminum, given a hard-anodized finish with knurling to keep bare hands from being rubbed raw.

Features:

• Manufacturer's page: Fenix TK22 V2.0
• Digitally regulated circuit for maintaining a stable output
• Low-voltage warning alerts when battery replacement needed
• Reverse polarity protection prevents improper battery insertion
• Anti-roll and anti-slip body design
• Instant power activation with momentary tactical tail switch
• Simple output selection with side switch
• Made of A6061-T6 aluminum
• Premium type HAIII hard-anodized anti-abrasive finish
• Toughened ultra-clear glass lens with an anti-reflective coating

Specifications:

• Output modes:
  Low: 30 lumens/80hr; 167ft (51m); 739cd
  Medium: 150 lumens/17hr; 400ft (122m); 3721cd
  High: 500 lumens/4hr 40min; 758ft (231m); 13356cd
  Turbo: 1600 lumens/2hr 10min; 1329ft (405m); 41133cd
  Strobe
• Dimensions:
  Length: 5.9” (150mm)
  Body: 1.0” (25.4mm)
  Head: 1.6” (40mm)
• Weight: 5.3oz (150g)(excluding battery)
• Battery: One 21700 rechargeable li-ion battery or one 18650 rechargeable li-ion battery with the ALF-18 battery holder (no battery included)
• Included: Body clip, lanyard, holster (length adjustable), spare O-ring, ALF-18 battery holder