Thus, an M2 x 0.4 screw has threads every 0.4mm. Although most metric fasteners have two or more standard pitches (fine & coarse threads), the pitch is often omitted from a thread callout; it is always helpful to carry a sample with you to the hardware store.
A tincture is a liquid extract made by soaking herbs in alcohol to extract the active ingredients from the herbs. Alcohol is considered an excellent solvent because it is food grade and can extract herbal constituents, such as resins and alkaloids, that are poorly soluble in water.
A tincture can be made of a single herb or a combination of herbs. Herbal tinctures are used because of their fast absorption and because of their long-shelf life. If the alcohol content of a tincture is a concern, glycerin extracts, capsules, or tablets may be used instead. Herbal tinctures are sold in health-food stores, some drug and grocery stores, and online. Some tinctures, such as arnica and compound tincture of benzoin, should only be used externally.