Hello. I am Ralph Wood -- I sell the Motor Guard submicronic bypass oil filter. They are a die cast aluminum filter designed to take a firm roll of bathroom tissue unrolled to make it 4 1/4" wide. They are not for every one. They require some mechanical aptitude to install. They work the same as the bypass filter on a 53 Ford flat head. The old engines had far superior filters and normally used cellulose such as cotton. At some point in time it was determined that it was better for a filter to filter a high volume of oil and remove only the larger particles than it was to filter slowly and clean the oil. It would have been better to have both the full flow filter and the bypass filter but that would have cost more. Normally a filter that cleans oil must be changed more often than the full flow filter but clean oil normally doesn't need to be drained. Some use an oil analysis program and others like me that have been doing it for a long time can pretty much tell by looking and feeling the oil if we have a problem such as a leaky head gasket. The design of the Motor Guard makes it the easiest and least messy to change of the submicronic bypass filter It is a compressing type filter which means it fills the element with waves to eliminate channeling. There is also less free oil in the filter at filter change to spill out. If the Motor Guard is in a place where it can drain it will empty at shut down. Cracking the tee handle will let air in so that the oil can get out if the air can't enter a hose. I have tried other submicronic bypass filters over the years. They all seemed to have problems such as being messy to change or leaks. The Motor Guard works perfect with two port sandwich adapters such as Perma-Cool that I get from <http://www.jegs.com>www.jegs.com. If you have questions my web site <http://www.bypassfilter.com>www.bypassfilter.com is very informative and is a secure place to order. The best time to call me is in the mornings central time at 866-283-2929, mention this forum.