The Brownells shotgun mainspring tool is engineered to expedite and simplify the process of replacing mainsprings in double-barrel shotguns, effectively reducing associated frustration. Its notched blade tip securely captures the plunger head, allowing for the compression of the spring and the removal of both components from the receiver without causing scratches or damage to the plunger or inner receiver surfaces, as might occur with a standard screwdriver. The tool is equally effective for installation purposes. To install, position the mainspring end in the receiver, align the blade notch with the plunger head, compress the spring and secure the plunger in the hammer. The tool's robust, hardened steel shank offers substantial leverage and ensures proximity to the work area for optimal control. Comprehensive instructions accompany the Brownells shotgun mainspring tool. The shotgun mainspring tool features precise dimensions - an overall length of 6-1/4 inches, a shank diameter of 0.3125 inches and a handle diameter of 1 inches, ensuring optimal performance and handling