Beware, they are junk in my opinion. I've been using Mobil 1 oil for over 10 years and swear up and down by it, it's the only oil I use. Their filters are something else. Last night I changed my oil and instead of using my usual Fram filter I decided to try a Mobil 1 filter, verified by me, salesperson (and backed up by Mobil catalog) at time of purchase to be exact replacement for my normal Fram PH3980. I changed the oil, filter, made sure everything was tight and then dumped in the normal 6 quarts of oil like I have numerous other times. I started up the car after I was done cleaning to go to the grocery store and within 1/2 mile the oil light came on, thankfully it happened right by a convenience store. I checked the dipstick and it was not even on the 'stick. I grabbed a towel from the trunk and got under the front end so I could see if maybe the drain plug was loose (even though I was absolutley positive I'd tightened it) and it was fine. I reached up where the filter is supposed to be and it was GONE! Somewhere between my house and 1/2 mile later the oil filter blew completely off of the mounting pad (and I know without doubt it was tight because I checked it two times before I dropped the car off of the jackstands) causing my engine to puke nearly 6 quarts of BRAND NEW Mobil 1 synthetic oil all over the road. I normally keep an extra quart or two of oil in the trunk and a spare filter (Fram) just in case of an emergency, thank God I did this time. I put on the spare filter, dumped in 5 quarts of cheap oil I'd just bought and fired it up, everything was fine. On the way home I saw the Mobil 1 filter laying up against the curb so I stopped and picked it up. It looks in excellent condition except for a couple scratches from sliding down the road at 35mph. Lets just say this has left me very pissed off to say the least. Not only did I waste over $40 on oil and filter but it could have cost me an engine and left me stranded in the middle of nowhere to top it off. I'm going to call them tomorrow and see what they do to rectify the situation. I am 100% positive that the filter was installed correctly and i'm going to check the threads with my digital caliper at work to see how they measure out. I'll let you know what happens.