Always clean skin meticulously, an acne skin is very sensitive. Eat a well balanced diet, avoid fatty food and take plenty of exercise, especially in the out-of-doors. Certain pure essential oil can be applied neat to individual marks-such as: 1  Tea tree oil. 2  Lavender oil.
The grain is a measure of weight. 1 grain is equal to 1/7000th of a pound. Or 7000 grains are in 1 pound. There are 15.43 grains per gram for those who are metric. It's just a weird way of saying how heavy something is in firearms. More grains means heavier bullet.
Metric threads are measured by the distance between two adjacent threads in millimeters (pitch). Threads on a standard (inch based) fastener are measured by counting the number of threads per inch. The tolerance system for metric threads is composed of a two sets of a number followed by a letter. The first set indicates the pitch diameter tolerance, and the second set indicates the major diameter tolerance.