Need some extra pizzazz for an upcoming project? This t popcorn pen set is absolutely perfect! All you do is write a letter in the paint-like ink, and it will puff up like in the above pictures! The set includes 10 colors! For optimal results using the popcorn pen, follow these simple steps: Step 1: Dry your colored ink with low heat from a blow dryer or fan for about 3-4 minutes. Step 2: Put the blow dryer on high heat and hold it close to the ink. Be patient! It will begin to pop after about 5 minutes. Step 3: Then ink will begin to pop! Just continue to hold the blow dryer over the ink until it looks just right. Enjoy! Product Dimensions (approximately): 5.5 inches in length.