credit: Xcor Aerospace
Four of these 5K18 engines will power Xcor Aerospace's Lynx suborbital spaceship. Detail about Lynx's development can be read here
The company's 5K18 engine test press release says:
The new engine, designated the 5K18, produces [up to 2900lb (12.9kN)] thrust by burning a mixture of liquid oxygen and kerosene. The engine was fired Monday, December 15th, 2008 at XCOR's rocket test facility located at the Mojave Air and Space Port. The first test of the engine was performed using pressure-fed propellants whereas the final version of the engine will be fed using XCOR's proprietary cryogenic piston pump for liquid oxygen and a similar piston pump for kerosene.