You can buy Green Advantage decals that can be used on a hard hat or other surfaces for $3 each. For bulk orders of 10 decals or greater, the cost is $2 each. Costs include shipping and handling.
To purchase decals, make your check payable to Green Advantage, note the number and type(s) of decals you wish to receive and mail it to:
Green Advantage, Inc.
P.O. Box 3170
Frederick, MD 21705-3170