most common size comparisons:

• A penny is 0.75 inch
• 0.75 inch stickers fit the bottom of a Hershey's Kiss
• A quarter is just under 1 inch
• An Eisenhower Dollar is 1.5 inches
• A classic Oreo is about 1.75 inches
• A classic Reese's cup is about 2 inches
• A tennis ball is about 2.5 inches
• A hockey puck is about 3 inches