550 Lumens; 17,000 Candela; Instant Activation Tact Switch; Up to 1 Hour of Runtime; Designed To Fit The Proprietary SIG Rail Found On SIG SAUER P365 Micro-Compact Line Of Pistols; User Configurable Modes: Momentary Mode, Latching Mode, & Threshold Mode; FlexCore Allows The Light To Be Powered By Either The Included Rechargeable RCR15270 Battery Or Standard CR2 Battery, Giving You The Flexibility To Choose The Best Power Source For Your Needs