I read pages and pages of reviews on what the best bed liner material is. Lots of opinions out there. I settled on Raptor. Made in the UK.
I ordered it from TCP Global via Amazon. It comes as a kit with 4 short quarts and one quart of activator. It's super easy, you just split the activator into fourths and add 1/4 to each container, put the lid back on it and shake for 2 minutes. It makes it easy, because you can mix up a little at a time.
After it is mixed you just screw the container on the gun and you are ready to spray. The higher the pressure, the flatter it lays out. I sprayed at 70 psi, which is the max recommended.