edit: looks like they give a pin for every gallon...

edit 2: yes, 8 gallons is more that is in a human body. When you donate blood they take 1 pint. over time as you continue to donate 1 pint at a time, you get to 8 pints - that is 1 gallon - Red Cross gives you a pin. Each time you make it to another gallon milestone you get another pin.

can we grasp that comms question now?

edit: looks like they give a pin for every gallon...