In nhãn s?n ph?m có r?t nhi?u ph??ng pháp ???c s? d?ng th?c t? trong ?ó in offset và in k? thu?t s? là ?ng d?ng ph? bi?n h?n. Chilly finger-A long copper rod extending along The within from the electron column. When its reservoir is retained filled with liquid nitrogen, the rod draws in contaminants Which may or else degrade the chamber's va