Vans Classic-Slip on shoes were first introduced in 1977. They were originally known as Style #98 and were a market leader in functionality, design and overall comfort.
The outsole gives an illusion that the shoe is thicker than it actually is. The full rubber section of the outsole measures around 3cm, but the insole sits significantly lower than that within the sneaker.
I discovered the actual height you gain from wearing Vans is just about 1.8cm brand new out of the box. The insole does have a bit of give to it, so after some wear, expect them to lose a couple of mm.