From SOFREP:

The first section of the article was aptly named “OSJ Bomb School” and provided step-by-step instructions on how to make a car bomb “…even in countries with tight security and surveillance.” The explanation was simple, the individual parts and pieces don’t raise concern when purchased or acquired but, when assembled they can create a devastating explosive device. The list of items that are said not to raise suspicion when bought individually include: epoxy, Christmas lights, barometers, gas grill propane tanks, and oxygen cylinders.