Vintage brass looking perpetual calendar

Vintage perpetual calendar. I am unsure if it's brass. It is very much art deco in in style. A fantastic addition to any desk or old style office. Side pull knobs on each side that pull half way and full to change day, both digits of the date and month. It has signs of once having felt on the bottom but removed. It has nice aged wear as seen in the photo and would look great with a polishing but some people like the aged patina look.