Aerio AWD L4-2.0L (2003)
3) Stamped number on piston and stamped mark on cylinder block should correspond. That is, install number 2 stamped piston to cylinder which is
identified with mark blue and a number 1 piston to cylinder with mark red.
Piston and cylinder specifications
Also, a letter A, B or C is stamped on piston head but ordinarily it is not necessary to discriminate each piston by this letter.