Safe 8 3/4 axle lift

It reminds me of those solid rubber wheel chocks. Same kind of rubber, I bet. The difference is, the wheel chocks have the ground to back them up.

Very similar kind of rubber I would imagine. And yeah, the chocks are limited/backed up by the surface they’re sitting on. And they’re not supporting the entire weight of the car, just whatever small component is coming from the angle of the ground or the car.