Iridium plugs have an extremely long life as Iridium is 6x harder and 8x stronger than platinum. Because of the strength and hardness of iridium, there is virtually no electrode wear. This combined with a platinum ground electrode, creates a spark plug that is almost impervious to wear even under ex...

The Ranger Handbook is mainly written for U.S. Army Rangers and other light Infantry units, however it should also serve as a handy reference for other U.S. military units as it contains a summary of other manuals such as FM 6-22 (FM 22-100), FM 3-21.8 (FM 7-8), FM 3-21.10 (FM 7-10), FM 3-90, FM 3-5...