Plastic is O.K. as long as you dont fuel up with them in the bed of your truck. They can generate static and when not grounded, can cause MAJOR problems. I have been using a 5 gallon plastic for my Lawn Boy for at least 5 years now and guess what (knock on wood!!) no explosions! I use Terene (sp?) Metal Eagle Safety Cans for all my straight gas for the other equipment. Also no explosions. here