Another famous creation from the Eames office is the one-piece molded fiberglass-plastic shell chair. Plastic, which is less rigid than plywood, can be molded with greater freedom. In the late 1940s, Charles Eames designed two types of shell chair, with and without armrests, and with several types of legs, including legs that allowed the chairs to be stacked. In the 1950s and 1960s, these chairs also inspired designers around the world.