Yup lewis. I have also used generic rippiffs of Lewis. Hoppes makes a close copy. I use them for my .45 Colts and Rugers and my Ruger .44 redhawk and various .357/.38. But only when they get really buggered up. If there is just a little leading it usually pops out with a bronze brush.
The first time I used one was on an old .45 that had been eating reloads for years.
You would not believe what came out of that “clean” barrel.