What clipper guard number is permitted for shaving the sidelocks?

Greetings, One must leave the hair of the sidelocks at a length of half a centimeter. This means cutting with a clipper that has a number 2 plastic guard, which corresponds to 6 millimeters (in Oster brand clippers; however, the length may vary with other brands). Sources: Pe’at Zakencha (page 30). Blessings, Hillel Meirs