I am the parts manager at a heavy Equipment Dealer. We are kicking around the Idea of offering refills for customer's oil packaging. 1 gallon, 2.5 gallon, 5gallon, and 55 Gallon. We have bulk oil containment and disbursement equipment and a oil lab on site. I test the oil into and out of the tank. Its filtered both ways. So the question is if you could save say 10-15% on your oil prices would you re-use your containers? This would be mainly smaller customers as large companies generally have bulk oil on site from us or another supplier.