... your reference 4.Full date OEM number Alu alloy truck piston Piston Material: ZL109 Aluminium Alloy, Alloy cast iron.Piston Type: 1 Steel-insert ... piston , 6 Compages piston , 7 Forged pistonPiston Feature : Satin Anodised Aluminium ,phosphating , Alfin ,Double Alfin , No Alfin , Graphite , Oil cooling channel ... : 79C: 245.9Pin Dia: 38 Length:92 No alfin Alu alloy truck piston