Received and excavated sources from early imperial China employ various terms for pieces of bamboo or wood that served as writing support. In many cases, neither the exact meanings nor diachronic differences in usage of these terms are sufficiently clear. What kinds of concrete objects the terms actually referred to in a certain period accordingly turns out to be quite an intricate question. This article focuses on the terms du 牘 and die 牒, which not only occur most frequently in the sources, but can also be considered as a complementary pair. Investigating differences in form and function that can be gathered from the way the terms are employed in both administrative documents and legal prescriptions of the Qin and Han period (including a newly published Qin ordinance) it argues that du and die were connected to two conceptually different types of manuscripts, namely single- and multi-piece manuscripts. It shows that these two types also entailed differences in how the manuscripts were kept for storage and transport, which were likewise reflected by special terminology. Finally, it proposes that the increasing use of multi-piece manuscripts instead of single-piece ones, especially since the time of Emperor Wu of Han 漢武帝 (r. 141–87 b.c.e.), probably had both pragmatic and economic reasons, which fit well into the setting of a gradually consolidating empire with an ever-growing volume of bureaucratic record keeping.