An inscription on a label on the box reads: 'wan ren collected by Chunzhai.' An inscription on the inner removable cover reads: 'The wan ren crossbow from Han dynasty was formerly in the collection of Ruan Yuan, and was recorded in his book, Ji gu zhai zhong ding yi qi kuan shi.' An inscription on the interior of the box states that the underside of the crossbow has an inscription, 'treasured by Ruan Yuan,' and that it was in Chunzai's collection.
This section of the crossbow is known as a guo, and several similar guo of Han date, along with a line drawing, are illustrated by Cheng Dong and Zhong Shao-yi, Zhongguo gudai binqi tuji (Ancient Chinese Weapons - A Collection of Pictures), Beijing, 1990, pp. 143-4, figs. 6-55 to 6-59, where one can see how they would have been positioned in the crossbow.