This is not a Drop-In part fitting is required please see the installation instructions: http://www.ghostinc.com/category/ruger_sr__rocket__tactical_and_all_other_connectors_installation_instructions/

The GHOST TACTICAL 5.0 lb for RUGER SR is our best trigger control bar reset with the TCT. It is the best for those who demand to be the best. This is the finest trigger control bar reset for all shooting activities, including law enforcement & self defense. The GHOST TACTICAL 5.0 lb is one of the Ghost family of trigger control bar reset that make your RUGER SR more accurate and more reliable by eliminating trigger over-travel and incorporating the self cleaning holes. This trigger control bar reset is amazing!