Protect large equipment and supplies from theft in Hallowell’s Single-Tier Bulk Storage Lockers. The ventilated steel lockers allow employees to see what’s stored inside without opening the door. Add locker tops and backs for additional charges. Create a row of lockers by attaching adder units next to a starter unit. Adder units have only one side wall and won’t stand alone, so you’ll need to order a starter unit for each row of lockers.