Hey Woot - some details on the product would be helpful.
I’m not sure, but based on the price and picture it looks like this MIGHT be Yogaslackers eLine Slackline Light Kit. If correct, this slackline is only 1" wide and is 15 meters in length. This kit does not contain the big protective tree straps that many kits include, but on the Yogaslackers website the guessed Slackline Light product does include two velcro straps that might protect the tree.
Hello. It was this one: