The closest match in my (rather old) reference is K40, with a half life of 1.248x109 years. But precision was lacking in the question.

There were some things that used to be measured in sixteenths of an inch - a sixteenth being a half of a half of a half of a half.

You can get precision rulers with inches divided into 32 equal parts. Most rulers give tenths.

Either less ripple voltage with the same filter capacitance, or similar ripple voltage with smaller filter capacitances (and thus physically smaller filter capacitors).

it means i precision you

Precision is a noun.