Kit includes Competition Hammer and Sear Pack, Trigger with overtravel adjustment, Buffer Technologies Shock Buff, 2 Hammer Shims, 2 Trigger Shims, Extra Power Hammer Spring, Extra Power Disconnector Spring, and Replacement Trigger Return Spring. Kit Includes:Ruger 10/22 Competition Hammer and Sear PackTrigger with overtravel adjustmentBuffer Technologies Shock Buff2 Hammer Shims2 Trigger ShimsExtra Power Hammer SpringExtra Power Disconnector Spring and Replacement Trigger Return Spring.Offers 2-3/4lb trigger pull.Highest quality EDM parts.Notes: Some Ruger 10/22 models will require the use of two Ruger hammer bushings for proper installation (product 510559). 10/22's that already have separate hammer bushings will not need new ones as the factory ones can be re-used.