The popular SIG P365 has a proprietary rail that prevents standard rail mounted accessories from fitting it. This CTL Custom was designed specifically for the SIG P365 by the expert engineers at Viridian. The CTL Custom for the SIG P365 is a compact 550 lumen light powerhouse an innovative weapon light, while embracing a refined, compact design and aesthetics to perfectly match the P365. The CTL is corner stone within Viridians C Series line of high performance rechargeable accessories, it offers an array of industry-leading features that ensure optimal performance and tactical advantage. NOTE: This device will not fit any other firearms.