Diamond Styli #ST120These are new synthetic CVD diamonds for cutting plastic discs and come with heating wires. These are known as our ST120 model, this is due to their 1: 20 conical shanks (known as 320) along with using 0. 12 nichrome heating wires, the slightly thicker wires require less voltage for sufficient diamond heat. They fit most modern cutterheads such as Vinyl Recorder, System Phonics, Flokason, or any other head designed to take 320 340 styli types. They