A rail integration system is a generic term for a standardized system for attaching accessories to firearms. Rail systems are straight mounting brackets on the gun's receiver, handguard, or fore-end stock to allow sliding or variable-position attachments. An advantage of the multiple rail slots is the moveable positions to adjust for optimal placement of each item for a user's preferences, along with the ability to switch different items at different placements due to varying eye reliefs on gun sights.

A tactical light or weapon light is a flashlight used in conjunction with a firearm to aid low-light target identification, allowing the user to simultaneously aim a weapon and illuminate the target. Tactical lights can be handheld or mounted to the weapon with the light beam parallel to the bore. Tactical lights can also serve as a non-lethal weapon, used to temporarily blind and disorient targets or, in the case of a large handheld flashlight, to be used as a blunt weapon.