Uzobona izinto ezifana ne-IIIA kanye ne-IV kusayithi lethu. Lokhu kusho amandla okuma kwezikhali zempi. Ngezansi uhlu nencazelo elula kakhulu.

IIIA = Ukuma kwezinhlamvu zesibhamu ezikhethiwe – Isibonelo: 9mm kanye no-.45
III = Ukuma kwezinhlamvu zezibhamu ezikhethiwe – Isibonelo: 5.56 kanye no-7.62
IV = Izitobhi zokukhetha izinhlamvu ze-AP (Armor-Percing) – Isibonelo: .308 kanye ne-7.62 API