The material is made out of canvas and epoxy basically. It is used a ton to make knife handles because it is impervious to chemicals, when it gets wet the canvas fibers stand on end and give you good traction and grip. They also make gears, and other manufacturing parts out of it. This material was first made to insulate high power electrical boxes because it does not conduct electricity. These are a full half inch thick so they are damn near unbreakable. The first two in the picture, and the whole second row should be legal in most every state, but you would have to check your local regs for the others. I used them is Aikido class all the time and there are extremely effective. I would with Kids who have behavior and mental issue and one of them flipped out and tried to attack me once so I have used one in a actual physical confrontation. I had the Kid (18 year old, 5'11' 165lbs) in submission shortly without really hurting him or myself. So they work good!
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