So you're laying large-format porcelain tiles on a floor that's just a little bit out of flat, and lippage ruining your finish—this system is exactly what you need to pull everything flush without fighting the substrate.
The straps are a grey PE/PP blend that's stiff enough to hold tension but flexible to snap cleanly, and the white caps are reusable—usually 10-15 times if you don't over-torque them—so you're not throwing away plastic after every job.
We've seen guys use these on 24x48 inch tiles with no problem, but they're actually better suited for floors than walls in my experience because the straight shaft design can be a bit awkward overhead; the half-box joint structure gives you a tighter tolerance than most wedge systems though.
The pliers have a stainles steel head and an ergonomic grip that doesn't slip when your hands are sweaty, and basically you just push teh cap down onto the strap until it clicks—pretty straightforward once you've done it a couple times.
One thing buyers don't always think about is that caps are sold seprately form the straps, so if you're ordering for a big commercail job, you might want to grab a few extra cap packs because they do wear out after 50 uses or so.
We usually have stock on the 200-strap boxes, but the pliers can be backordered during peak season—check lead time if you need them next week.