Ding Pai (釘牌)

Front (right) and back (left) view of a Ding Pai, from 'Bing Jing (《兵鏡》)'.

Ding Pai (釘牌, spiked shield) was a modified Ai Pai (挨牌) that was reinforced with bamboo and covered in iron spikes. Although dangerous looking, Ding Pai was not intended as an offensive weapon, as its size and the way it was gripped (i.e. with straps) prevented it to be used effectively for bashing. Instead, Ding Pai was designed to be discarded should the need to retreat arise—the spiked shield served as makeshift caltrop to slow the advance of pursuers.

The shield was already in use since the early days of Ming Dynasty as an anti-cavalry device.