4th Generation smart selector ring and tactical dual buttons on the tail are applicable for one-handed control of all different modes.Ultimate dual tail buttons and ultra strong strike bezel are specially designed for tactical applications.2100 lumens invincible performance & 510 meters max. The 5000 mAh NL2150HPi battery is included, SRT6i is with USB-C charging port, charging time only 3 h 15min.IP68 rated, 2 m impact resistant. Anti-impact reverse polarity protection mechanism.