Those are Hogue Bantam grips-they do make other variants for that Ruger in their Monogrip line I believe.
I had the Redhawk in .41 mag in blue with the 5 inch barrel and could never come up with a set of grips that worked for me-short trigger finger means large grip frames are a no go.
I found a set of grips from Altamont that use the factory OEM plastic insert that were better.
My local store has a Super Redhawk in .44. I'm thinking of picking it up so I can load some serious rounds. I gave a super Blackhawk but that apparently isn't as robust as the Redhawk. What have you put through yours?