The Viridian R5 Gen 2 green laser sighting system is easy to install and blends seamlessly into the trigger guard for invisible profile and smooth draw. Viridian's green lasers utilize a 510-532nm wavelength range creating an optimum target dot that is up to 50 times brighter than red lasers. The gen 2 models include 3X more battery life (up to 5 hours) and an INSTANT-ON ambidextrous, inside the waistband (IWB) holster with automatic laser activation. Made of microfiber, this holster is more comfortable and durable than the previous models. This model is compatible with Glock 42.