1. MidWest Homes for Pets Wire Mesh Top for Exercise Pens (Click Link to Check Price on Amazon)
Editor's Rating : 8.8 out of 10
Fits any 4x4 foot pen9 and 11 gauge wire with 1.5" X 6" spacing

2. ToysOpoly Pet Playpen 45" Exercise Puppy Pen Kennel - Best for Dogs and Cats Safe in Their Play-pen While Protecting The Little Kids - Folding Design Easy Storage (Blue) (Click Link to Check Price on Amazon)
Editor's Rating : 9 out of 10
SUPERIOR VALUE: RECEIVE BONUS ABSOLUTELY FREE! **Limited Quantity!** This complete bundle includes: 1 tent + 1 zipper top with sunscreen protection + 1 zipper bottom and 4 stainless steel anchors.YOUR PET'S SECOND HOME - Your pets will fall in love with this large, spacious tent! They will grow accustomed to it and even treat it as their second home! You can really personalize your pet's tents by adding in blankets, comforters, and chew toys!

3. OxGord Metal Wire 8-Panel Folding Exercise Yard Fence for Pets, 42 Inch, Black (Click Link to Check Price on Amazon)
Editor's Rating : 9.1 out of 10
Buy a Trusted Brand Name - Oxford is the #1 Top Rated by Consumers when it comes to Pet Supplies & AccessoriesCollapsible: Easy to Set Up, Break Down, and Transport

4. EliteField 2-Door Soft Pet Playpen, Exercise Pen, Multiple Sizes and Colors Available for Dogs, Cats and Other Pets (30" x 30" x 20"H, Maroon+Beige) (Click Link to Check Price on Amazon)
Editor's Rating : 9.2 out of 10
Size: 30" x 30" x 20"H a free carrying bag and 4 free ground stakes included

5. PET EXERCISE PEN with Cover - Lucky Dog (24" High x 6' Diameter) (Click Link to Check Price on Amazon)
Editor's Rating : 8.9 out of 10
PET EXERCISE PEN WITH COVER - The wire design is built to keep your happy pet in a safe and secure area. Perfect for dogs cat and cats large and small.INDOOR/OUTDOOR USE - Use this wire excersise pen in your house or out in the yard. Every unit comes with anchor pins, installation clips and cover