In the event of an earthquake, fire or other emergency, your pets will be especially vulnerable. You may not be able to get home to feed them or they may be trapped inside.
A sign posted outside will help alert emergency workers and/or your neighbors.
The most effective protection will be provided if you make sure your closest neighbors, next door, BEHIND and across the street know your pets by sight. Likewise, a collar with an ID plus an embedded microchip are vital to eventual recovery if lost.