Bolt tensioners are devices designed to apply a specific tension to a bolt. The device may be either removed once the actual nut is threaded into place, or left in place, in the case of a hydraulic nut.
The metric system does away with all of the different units of volume used in the English system, and instead, uses only one unit to measure volume. That unit is called the liter. Materials Needed: Meter stick or metric ruler; stiff cardboard such as poster board; scissors or hobby knife; tape.
For liquids: the same thing as you have in your kitchen, basically. Pipettes are used for small volumes. To measure the volume of gases, a gas syringe can be used, see picture below. For solid objects, the most accurate method is probably to attach the object via a string to a hook and suspense it in a glass (filled with some liquid) on a weight.