KSI
KSI is an abbreviation of Kilopound per Square Inch.
which is used to measure pressure. It is actually equal to 1000 psi (pound-force per square inch/ lbf/in^2). psi is a British unit defined as the pound-force (force exerted by gravity on a British pound) exerted on an area of one square inch. ksi is not widely used to measure gas pressure, but it is used primarily in materials science to measure things like tensile strength (maximum stress an object can withstand), which is measured using a large number of 'psi'.
