One Calf Stall Starter Pen is needed for each row of calf stalls. The Starter calf stall has two side panels. Each add-on stall has one side panel because it shares a side panel with the stall before it. The entire calf stall is completely coated with durable plastisol (polyvinyl). The vented sides allow air to flow through easily, while solid sides prevent unwanted drafts in colder climates. The Dura Trac Clearspan expanded metal and woven wire calf floors offer superior footing. The calf-appropriate mesh size aids in traction. For calves up to 300 pounds. Custom sizes available.