This is a Ruger Moon Clip chambered in 45 ACP, model 90483.
These full moon clips are made from stainless steel and function as a speed loader. They feature an optimized charge hole design for positive ejection over a wide range of ammunition. Ruger full moon clips act as a speed loader for quick reloads and the design allows for loading and unloading without the use of a moon clip tool.
Features:
Faster Reloading
Steel Construction
Fits Ruger Redhawk in .45 Auto/.45 Colt