This kennel uses thin wall 20 gauge  tubing.  The kennel has 12 gauge chain link fence stretched within the frame. Reasons why this kennel does not come with 9 gauge chain link fence is because if you tried to stretch 9 gauge fence in this frame it would ( A. ) Pull the gate clips off the fence. ( B )        Pull the tension rod out of the clips. ( C  ) Collapse the frame.  ( D ) All of the above.  This Kennel uses a 3/16 or 1/4 inch thick galvanized round rod in the place of a real tension bar which is flat.         When I google fence tension bar I had no luck finding anyone that even sells this small round rod,  even though I know you can purchase it at your local steel supply.  Kennel #1 uses gate clips that are only bent like a hook instead of tension bands that wrap around the post and have a hole in them then a bolt goes through the hole with a nut to tighten. The frame only has feet on each end post so 2 per panel so no middle support . In the descriptions for a Gold Series Complete Dog Kennel that cost $419.99 the Product Weight is 195 Lbs. This kennel does not have a cross in the middle of each panel ( the red line drawn in the middle of the frame represent the cross  )which would be part of the frame and help make the frame stronger. The Gold Series Complete Dog Kennel does have the cross and that's probably the reason it cost roughly $100 dollars more. These panels are the same as your cheaper temporary fence panels placed around construction sites to keep people from walking on the jobsite and getting hurt but will not stop anyone who really wants to get onto the property. The same is true with this kennel it will provide boundaries for any dog but will not contain many dogs once they want to get to something on the other side of the fence, weather it be to simply get out because it doesn't like being in a caged or there is something or someone it wants to get to or play with. Some descriptions say this is for dogs up to 120 lbs and Gold Series is for ALL Sizes. So if they all have 12 gauge chain link  and I have seen pictures where a 30 lb to 50 lb dog eat a holes in the fence dogs like a Blue healer or Border collie.  So what happens when you put a Pit Bulls, Rottweilers, any type Mastiff or Malinois in a cage like this well if the dog is aggressive in an way your looking at a accident waiting to happen.