I think this is slightly dangerous. The product is well made, no doubt. It looks fantastic, no arguments. Is it safe Probably not without supervision lol. Its like taking your child to the playground...youre going to watch for safety the entire time. The two horizontal boards on levels 2 and 4 are slippery (as others mentioned) and my cat has zero grip to stop. Hes seems so scared of falling that he wont go on it. Also, those horizontal boards are a few inches short. They should be 27 or 28 x 13, instead of 24. The current measurement make it difficult for cats to go updown a level safely...at least in my observations. Since it was 100, Im not giving up. Im going to buy and attach a couple of towel  shammy dog mats to the wood to see if that helps. Otherwise, this bad boy is going back lol.