If you have 2 good trees, measure up, you can suspend a Slackline between them, Our 2Tree Kit includes a line of 10m length, or 20m length.
It's more likely that you have one good tree to secure one end of a Slackline, and you will use an A frame at the other end. Our 1Tree Kit includes this frame and a 10m line.
No Trees? No Problem, set up your slackline using the 2 A frames in the NoTree Set which includes a 10m line.