Features of Fenix TK25 RED: Cree XP-G2 S3 and XP-E2 red Led’s with lifespan of 50,000 hours Powered by one rechargeable 18650 Li-ion battery or two CR123A Lithium batteries 142.6mm Length x 25.4mm Body diameter x 40mm Head diameter 156.5 grams (excluding battery) Rotary flashlight head for free switching between white and red lights Compatible with AER-03 remote pressure switch Digitally regulated output maintains constant brightness Reverse polarity protection, to protect from improper battery insertion Tactical tail switch for momentary on activation Functional tail switch for output selection and instant strobe Made of durable high-strength and oxidation-resistance aluminum Premium type HAIII hard-anodized anti-abrasive finish Toughened ultra-clear glass lens with an anti-reflective coating