I was looking for a lightweight footrest I could put into my gig bag to take it with me to use it during lessons. This one is really light thanks to a clever combination of rigid plastics and some metal. It can be adjusted at several levels, with the lowest only 10.5 cm / 4.2 inch above the ground, which I like very much.
Why not 5 stars, then? Because the top of footrest is always level to the ground, I'd find some slope more comfortable.