I've seen it, but not for a long while. Castle products used to be fairly common around here as they are almost local, but I've noticed them dropping off the shelves quite a bit from the Mobil gas stations and Wilson Farms mini-markets. I can't say how their oil treatment is, as I've never heard of anyone actually using it. They used to package it with the excellent fuel injector cleaner (Fireball and Fireball Plus) and a tee-shirt. Their other products, are pretty good quality, the auto glass cleaner is especially heralded here...