The same great poster  - digital. You can duplicate unlimited quantities in any size. You download the graphic and "Permission to Duplicate" letter and print it to your custom size!
 
Simply send a clear message that you value your volunteers.  Maybe a letter size or poster size paper with a hand written note saying, “We thank you for caring for our patients that need a friendly face to care for them”
 
Ideal Dimensions are 13” X 19” or smaller.