Ruger Standard, Ring, 30mm Extra High(6), Matte Blue Finish, 6B30, Sold Individually 90323
Specifications:

Type	Ring Single
Tube Diameter	30mm
Height	Extra High
Size	Accepts up to 62mm
Finish	Blued
Style
Material	Alloy
Style Description
One or Two Piece	1
Adaptor Type
Mount Type
Lock Type