Everything went easy when I cranked my compressor up to 90psi. I used a Kellsport Fluid Film & Woolwax Undercoating spray gun with extension to apply. Oh yes, when I put it on, the outside temperature was about 70 degrees. I'll update over the summer to say how well it's holding up after the winter salt. Update, it's been about 7 months. It's been a very salty winter in my area. I crawled under a car and SUV that I had sprayed with this product and both showed no signs of new rust. I can say that this tool works well for my car.