Businesses have counted on the Dri Mark Counterfeit Money Detector Pen for over 25 years you can too! Choose from a variety of pack sizes perfect for small and medium sized businesses that want an efficient option for loss prevention related to counterfeit U. S. currency. These are easy to use just put a small mark on the bill being presented to you. If the ink remains yellow, you know this is real U. S. tender; if it turnsyou immediately know not to take the bill. It is that easy and super fast. Instantly And Easily Detect Fake Bills - Prevent profit loss with this fast, accurate, effective counterfeit tester; Marker pen detects genuine US currency paper; Simply draw a mark on a dollar bill: dark mark means fake; light mark passes test; Includes 1 Checker Pen. Dri Mark Pens will outlast and outperform others made offshore; Precision fitted parts ensure long shelf life and no-dry-out if recapped; The Dri Mark Counterfeit bill detection pen is the original and is still the top quality, USA-made checker; Trust the original; Accept no substitute. Smaller Pen, 3 Times The Ink - Dri Mark's Full Size Counterfeit Bill Detector Pen has 3 times the ink and is almost an inch shorter than previous models; Designed for Small to Large businesses such as restaurants, banks, retail stores and entertainment venues. Top Quality U. S. A. Made - Dri Mark is the only US manufacturer and original patent holder of Counterfeit Detector Pens; For over 25 years, the most widely used point of purchase deterrent against loss due to fake money. Manufacturer 100% Money Back Guarantee: Dri Mark's 90-day Limited Warranty from the date of purchase; You can trust Dri Mark's money marker counterfeit pens for fast and accurate results. Dri Mark Counterfeit Bill Detector Marker Pen, Made in The USA, 3 Times More Ink, Full Size, Fake Money Checker - Money Loss Prevention Tester & Fraud Protection for U. S. Currency, 1 Pen.