Richard Serra's Prop Series, initiated in 1969, represents a significant phase in his exploration of sculpture's fundamental elements—balance, weight, and gravity. These works are often seen as precursors to his later large-scale metal sculptures, for which he is most renowned. The series consists of various pieces that rely on their own weight and gravity to stand, creating a tension between the sculpture's components, such as in the work "One–Ton Prop (House of Cards)," made from four lead plates leaning against each other​ (Guggenheim Bilbao)​.

This series marked a departure from traditional sculptural practices by eliminating the base or pedestal, thus altering the relationship between the artwork, the space it occupies, and the viewer. Like his minimalist contemporaries, Serra used industrial materials, uncommon in sculpture at the time, to probe these relationships. His interest in the physical properties of materials, such as lead, and their reaction to external conditions like gravity or temperature, has continued to characterize his work. The Prop series, in particular, showcases Serra's fascination with the process of creation and transformation of materials, a theme that runs throughout his career​ (Guggenheim Bilbao)​.

From the early stages of his career, Serra was interested in how sculpture could engage with its environment and alter the viewer's perception of space. His move towards using steel in the 1970s and beyond allowed him to create sculptures of a scale that demanded to be experienced by moving around and through them, further emphasizing the physical and visual relationship between the artwork and its surroundings. This shift towards site-specificity and engaging the viewer in a bodily experience of sculpture is a defining aspect of Serra's legacy in the art world​ (The Art Story)​.