Crimson Trace : 01-6401-1 Integrated Green Laser for the S&W M2.0 Shield
This product is the replacement components for the Smith & Wesson M2.0 Shield with integrated Crimson Trace laser. This replacement kit will only work with your pistol if you purchased it with an integrated laser, which has a special frame to house the laser.
If you're looking for a laser to attach to your S&W M2.0 Shield that did not come with an integrated laser, see the LG-489G Lasergrip.