Realty Income (O) is a large REIT with over 15,500 properties. They mostly do single-tenant retail for essentials like grocery and convenience stores, where tenants pay most operating costs. Their balance sheet is investment-grade and occupancy stayed above 96% during the Great Recession. The stock pays a monthly dividend with a 5.1% yield. It is a slow moving stock, but they have raised their dividend by about 4.2% annually for 31 years straight. It could be worth a look if you want stable passive income.