Prevailing during the Warring Period, Qin and Han dynasties some 2000 years ago, a Tiger Seal was the symbol of power. The emperor granted the authorization to assemble army to generals by giving him a tiger seal. Usually made with copper, a Tiger Seal splits into two parts from the middle; the emperor keeps the right half, and gives the left half to local officers. The body of seal decorated with given characters and pattern claims which part of army the general could control. When the army is needed to assemble, the emperor gives the right part of Tiger Seal to one general. When the general meet up with the local officer, he can show them his part of the seal and claim control of the local army.