Designed for use on subcompact handguns like Sig Sauer's P365 and P365XL, the ROMEOZero is a micro red dot sight that will take your shooting to a new level. It's ultra-compact WeaponsGrade™ polymer body is optimized for concealed carry with no sharp or catching edges. The lens is Sig Sauer's own SpectraCoat™ HD lens system and provides a clear dot and sight picture. The red dot is activated using Sig's Motion Activated Illumination System that turns the unit on when it senses motion and powers down when idle. When used as intended the battery life of the RomeoZero Reflex Sight will last up to ten years, but the CR1632 battery is replaceable and the sight body features a rear backup sight.