Wash. Rev. Code § 36.49.020
The county assessor shall turn over the list of dog owners to the county treasurer for collection of the taxes. Upon the payment of the license tax upon any dog or kennel the county treasurer shall deliver to the owner or keeper of such dog or kennel a license, and a metallic tag for each dog taxed and licensed or kept in such kennel. The license shall be dated and numbered and shall bear the name of the county issuing it, the name and address of the owner of the dog or kennel licensed; and if a dog license, a description of the dog including its breed, age, color, and markings; and if a kennel license, a description of the breed, number, and ages of the dogs kept in such kennel. The metallic tag shall bear the name of the county issuing it, a serial number corresponding with the number on the license, and the calendar year in which it is issued. Every owner or keeper of a dog shall keep a substantial collar on the dog and attached firmly thereto the license tag for the current year.
RCW 36.49.020