Zip Line Seat or Harness?
When deciding between a zip line seat or harness it is important to consider how your zip line will be used and the ages of the children who will be using it. I generally recommend the zip line harness for kids under the age of 7 because it secures them in the harness so they cannot fall out or fall off like they could with a seat.
A harness is also a good idea if you're going to be building a platform for your zip line, it's always safer to use a harness if your platform is more than 4 feet off the ground. The use of a tow rope with platforms is also recommended. (The Alien Flier Zip Line Kit with Harness is shown above) For kids older than 7 years old you could use either a disc seat or a swing set style seat. The only difference here is where they will be holding on, with a disc seat they can hold onto the zip line trolley because it has handlebars, but with the flexi seat they can hold either the nylon coming up from the sides or the trolley.
If you're an adult looking to zip line I recommend or ZLP zip line kits, they hold weights up to 350 pounds and offer adult zip line harnesses and other attachments.