If you are looking for a light for your Sig Sauer P365 or P365XL, check out the SureFire XSC-P365…
The SureFire XSC 365 is a rechargeable 350 Lumen pistol light made to fit onto the rail of the Sig P365 series of pistols. It comes with a removable rechargeable battery, with indicator lights, as well as a Micro-USB Charger. It is activated by paddle switches on the left and right. Featuring momentary or constant on settings.
The light is pretty well supported, to include most of your better holster manufacturers like Black Point Tactical. For my own part, I’ve been carrying it quite a bit in a FO3 Holster by BP Tactical.