Just for information sake: Humane offers the puzzle type connections on all all of their animal (horse, pig, cow, dog, etc...) mat and stall mats (even their industrial and exercise mats). This puzzle connection is a great way to keep the mats together. As an example the stall matting when laid and installed correctly can move with horse or animal movement. Not only is the a pain to keep track of but can be dangerous. With that said, Humane does offer the matting with three different sides to them. One is a right out of the mold (don't forget Humane has one of the best molding processes for a superior product), this is a straight edge or flat side. The Second option is what is called a True Edge, this edge is a precise or very straight water jet cut. This straight edge fits up next to other True Edge mats perfectly. And of course the Third are the Puzzle Connections.
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