Sentence:  The scaler looks at the order ticket and selects a shipping container or containers of proper size to hold the <WSD>catchweight</WSD> items or those of 12 pounds or less. The <WSD>catchweight</WSD> items are weighed, marked, and placed in the containers. 
Meaning of the word marked with <WSD> tags:  Having no standard weight, but rather having weight determined when packaged for sale or shipping.