Features: This spies pen lets you write secret messages which are only reveal by the light! This invisible ink pen is a perfect gift for children. They can use the pen to uncover secret messages. Children love forensic spies game and these pen make a perfect addition to any spies collection box. Shine the light on the writing spots to see messages appear like magics! A perfect party gift allowing your children to be really creative with their writing, sketching and drawing. Specifications: Component: Plastic Size: about 12x20cm/4.72x7.87'' Type: 2 Kinds Optional Package Includes: 2 Kind Package Optional as Follows: Package 1: 7 Pcs/Set Invisible Ink Pen Package 2: 14 Pcs/Set Invisible Ink Pen note: Please allow 1-3cm errors due to manual measurement. Due to the difference betweeen different monitors,the picture may not reflect the actual color of the item.