A nut member has first and second end faces and corners, and is formed with a plurality of protrusions, each of which is disposed at a respective corner and each of which has a lateral inner face that extends from the second end face, and a plurality of recesses, each of which is indented inwardly from a respective corner and each of which is defined by a recess-defining wall. These reaction products are useful as lubricant additives for oil-based and water-based functional fluids. In one embodiment, the measurement adjuster increases the number of samples for determining the weight of an item.