how it is usually done in the fulfillment industry is a scale that changes the track if it is off weight by more than a certain percent (think of how train trac

how it is usually done in the fulfillment industry is a scale that changes the track if it is off weight by more than a certain percent (think of how train tracks work). The problem here is tougher than just a toothpaste factory because you can have multiple items in one purchase order and you have to make sure all items are in the box. Stopping the entire line every time something is off with 1 package is never a good solution. With pushing the packages into a 'problem' pile, someone can figure out what is wrong with each one and get things moving again on their own schedule.