what are cartridge needles?

Cartridge needle refers to a type of tattoo needle that is composed of a replaceable head and is designed for easy and convenient replacement and cleaning. Cartridge needles typically consist of a fixed shell and a replaceable core, with the core containing the actual piercing part of the needle, and the shell responsible for connecting the needle to the tattoo machine. This type of needle is generally considered safer, more hygienic, and more convenient than traditional non-replaceable needles.