The function of the element is to meter and deliver the metered fuel. Element consists of barrel and plungers. The rotary motion of the plunger inside the barrel regulates the quantity of fuel and an upward motion delivers the fuel. The plunger is precisely fitted to the barrel with very small clearance to form a perfect sealing. They should be replaced as a set. (barrel and plunger) And part numbers of all renowned brands such as BOSCH, Zexel, Denso, Delphi, Ambac, Mico, Usha, Lucas-Cav, Diesel Kiki, Nippon-Denso, Motorpal, Lucas, Cummins,Yanmar, Doowon, Stanadyne, Caterpillar,Nippon Kiki, CC Diesel,7Diesel, Gamma Diesel, Diesel power,Omap Diesel, Mtu, Komatsu, Toyota, Susuki, Nissan, Mazda, Honda, Hino, LL Diesel etc.