Alpha Dog Series 6 Piece Plastic Playpen 6 PIECE SET MODULAR PLASTIC FENCE; ADDITIONAL "SET" FENCES CAN BE PURCHASED TO MAKE A BIGGER PLAYPEN CAN BE DESIGNED ANY WAY YOU WANT IT TO YOU AS LONG AS THE BLOCKS CONNECT GOOD FOR BOTH CATS & DOGS USE AROUND YOUR HOUSE TO KEEP YOUR PET IN A SPECIFIC AREA CAN BE USED A BARRIER TO MAKE SURE YOUR PET DOES NOT GO AROUND WHEN YOU ARE NOT HOME