At unstaffed Federal recreation sites you may need to display your pass or show proof of pass ownership to compliance officers via one of the two following methods:

• HANGTAGS
  A pass can either be displayed on your rearview mirror using a free hangtag or on your dashboard with the signature side showing. Remember, the hangtag itself is only a way to display your Pass, and is not valid for entry unless it holds a valid Pass.
• Every Kid Outdoors Voucher
  A valid Every Kid Outdoors Park voucher can be displayed on the dashboard of the vehicle with the bar code showing if it hasn’t been exchanged for the Annual 4th Grade Pass.