Arm & Hammer is a registered trademark of Church & Dwight, an American manufacturer of household products. The logo of this brand is a depiction of a muscular arm holding a hammer inside a red circle. Originally associated only with baking soda and washing soda, the company began to expand the brand to other products in the 1970s, using baking soda as a deodorizing ingredient, including toothpaste, laundry detergent, underarm deodorant, and cat litter. The Arm & Hammer brand is one of the longest-running and most recognized U.S. trademarks.