The Sir Tools spring compressor is designed to be used with an impact wrench. It is also designed to compress the spring on the car to save time. It does not work on all cars, but many.
Being careful and thinking about what you are doing, in regards to safety helps prevent injuries. Release spring tension slowly and methodically, depending on the type of spring compressor being used. Maybe watch an instructional video on the tool you are using, or get some help from someone with èxperience.
I have checked out several types of spring compressors, I had planned to get the Sir tools compressor, but I would really like to see the hydraulic version.
Please a picture, link, or info on the hydraulic spring compressor.