This webbing harness is made with a loop of webbing clipped in the front with a carabiner.
If your loop is too big or too small, you'll have to adjust the size of the loop and start over. However, once you have the loop the correct size, you can quickly put on and take off the harness with no knot tying.
The main advantage of this type of harness is that you can quickly take the harness off and on without tying lots of knots.
We use this a lot at home when we have 20 kids that want to ride the zipline but don't have enough harnesses for everyone.
Like other webbing harneses, this webbing loop harness is not very comfortable and has no padding. It's also not adjustable.