Weapon Lights

A weapon light exists so you can identify a target before deciding whether to shoot it, which makes it a safety device as much as a tactical one. That framing also explains why it does not replace a handheld light: anything you point the weapon light at, you are pointing the muzzle at.

Mounting and switching are the whole purchase. On a handgun the light has to fit the rail and the holster you already own — most holsters are cut for a specific light model, not for lights generally. On a carbine, place the switch where your support hand already rests rather than where the light happens to sit. And check the light is rated for the recoil of the host; pistol recoil kills lights not built for it.