How does this help me lift my car more safely? I thought it was a pancake size thing...not a roll of quarters. Why would displacing the force over a small area be better than my jack?

 

I could be wrong, but I think the smaller side slots into the hole in the jacking point of the car and the wider side fits nicely into your jack's pad.

 

Insert the small end in the jacking point and twist it. The prongs will keep it held in the car and you can then raise the jack up to the bottom of the device which will give a flat surface to the jacking point and the jack. I made something similar to fit on the end of steel beam to lift the whole side of the car.

 

It prevents the car's jack point from sliding off the jack. Pin locks into the jack point, circular base is contained by the circular metal pad w/ lifted edges on most floor jacks.

 

I have the same ones. Prior to having them, a shop jacked my car without them and destroyed the plastic shark fins on the rear sides. I was lucky they didn't do more damage.

 

Agreed, I was looking at the one you bought but a couple of members told me that it had a deceptively small footprint. The Rennline one appears to be wider and more appropriately sized.