Bronze vessels were items of luxury and power throughout the entire Zhou period, and changes in the types and decoration of these vessels illustrate the many cultural and political shifts that characterize this long and complicated era of Chinese history. The experimentation with shapes and abstraction of designs seen in the latter part of the Western Zhou continues throughout the entire Eastern Zhou period. The shape of this canteen, now often called a "pilgrim's flask" (bian hu), became popular about 400 BCE. New methods were used to decorate this flask. The primary embellishment consists of square panels filled with an abstract interlaced design, a motif often called "hook and volute." These decorative panels were created using molds that were stamped rather than hand-carved. In addition, the raised areas between these panels and the triangular forms decorating the neck were inlaid with a reddish copper; the use of this inlay helps to date this vessel to the 4th century BCE. The use of copper inlay in this canteen heralds the importance of inlay as the primary decorative technique in Chinese bronzes made from the 5th through 3rd centuries BCE. Although this type of decoration differs from that found in earlier Chinese bronzes, the methods of manufacture remained unchanged. The bronzes were cast with depressions that were later inlaid with several materials: turquoise, copper, silver, or gold.