Contains 4 each of 1/4″, 3/8″ and 1/2″ packed in a fancy counter display. Display takes up just three square feet of shelf space Socket trays come in SAE and Metric sizes for 1/2″, 3/8� or 1/4″ drives. They’re molded of rugged ABS plastic to shrug off lubricants, solvents and abuse. Display holds four trays in each of the three SAE sizes and three Metric sizes