These are the jacks I have.. The blue one is a 1.25 tonne and the red one is a 2 tonne. Both are low entry so will go under very low cars and both are aluminium so easy to haul around..
The Adaptor shown has a deeper groove cut as it was cut especially for my car while I will cut a fresh one with less depth for the Wife's Fiesta but it gives you the idea..
Once the adaptor is in place and jacked up under the car there is no way it can move. It really is a very stable platform and a safe way to lift your car without the possibility of doing any damage !.. I have used these for many years on a variety of cars and vans and have never had any issues at all.
BTW Both of the jacks pictured are from Costco.. The red 2 tonne one is on offer at the moment at £107 inc VAT. OK you can buy cheaper but hell are these tools built well and a joy to use !