For 18-19 Softail - Polished. Screws into the factory oil fill spout as a stock replacement part on M-Eight Softails. This breathing dipstick removes unwanted build-up of blow by, which is found in engines with excessive leakdown through the rings/cylinders which is a common issue with large displacement big bore engines. Test results show a decrease in engine sump oil levels. Dipstick vents excessive pressure from the oil tank through a breather system consisting of a filter element and umbrella valve. Choose from two venting style options when installing the dipstick. Option 1 is to use the 1/8 NPT breather vent fitting with internal porous filter element (this option gives a clean look; however it can produce an oil misting/residue out of the element on engines with excessive leakdown/blow by). Option 2, is to use quick-disconnect coupler fitting with rubber hose and filter element (this option will run any excessive oil misting/residue through the line and into the filter element, but does requires disconnecting the fitting in order to check the oil). For option 2, we recommend routing the line up the frame rail, up under the seat/abs area then back down along the right side frame rail and the filter element can fit cleanly between the engine/trans matting area on the inside of the lower right frame rail. There are two ways to read the oil level with this dipstick, with the bike on the jiffy stand (FHS) or the bike upright and level (FHU). If reading the dipstick with the bike on the jiffy stand you will take your reading from the dimples labeled FHS (Full Hot Stand). When reading the dipstick with the bike upright and level you will take the reading from the dimples labeled FHU (Full Hot Upright). Made in the U.S.A. The oil pick-up port is on the right side of the engine. Letting the bike idle or warm up on the kickstand will naturally fill the engine case and skew the oil level in the tank. - Part Number - 0710-0261