A dumpy level, also known as a builder's auto level, leveling instrument, or automatic level, is an optical tool used in surveying to measure horizontal lines.
The electrical submersible pump, typically called an ESP, is an efficient and reliable artificial-lift method for lifting moderate to high volumes of fluids from wellbores.
The Extension Ladder is a non-self-supporting portable ladder that is adjustable in length. It consists of two or more sections that travel in guides or brackets so arranged so as to permit length adjustment. It is intended for use by one person.