Shot Glance Liquor Inventory Rulers Accurate - Measurements Can Be Taken In Any Increment Desired Fast - After A Bit Of Practice 60 Bottles Can Be Measured And Recorded In 10 Minutes Easy - A Short Learning Curve. No Intensive Training Needed To Become Proficient No Maintenance - High Quality and Durable Material Does Not Break Down Portable - The Shot Glance Bar Inventory Control System Moves With Temporary Bars and Catered Events