The steel Mark 4 cross-slot mount is designed to fit a Picatinny rail. Mark 4 rings offer superior integrity and tighter tolerances that are based on the proven cross-slot design.
Specifications:

Type	Ring Set
Tube Diameter	30mm
Height	Super High
Size	1.4"
Finish	Black Matte
Style
Material	Steel
Style Description
One or Two Piece	2
Adaptor Type
Mount Type	Picatinny
Lock Type