I hooked up a 3D printer tool head and needed small connectors that I could buy somewhere like Digikey or Mouser. But overall they were cheaper considering the premium shipping. Also, I bought a Microfit kit elsewhere but it didn't have a 6 pin 2x3 connector so I got these. They were authentic and of the same quality as the ones in my kit. You need a crimping tool. I used IWISS IWS-2820M AWG 28-20 (B078WNZ9FW) crimping machines and everything went fine.