Review on 🔌 Haitronic 120pcs 20cm Length Jumper Wire/Dupont Cable Multicolored 10 Color M to F, M to M, F to F Each 40pin for Prototype Breadboard DIY Raspberry Pi 3 4 Orange Pi BBC Micro:bit Makey Makey by Johnny Price

The conductors in these wires are Copper Clad Aluminum (CCA), NOT "Material: High Quality Copper Core". as indicated in the description. This is a big problem if you want to take apart and solder some to make Y-connections and the like. You just can't solder CCA like that. The tiny layer of copper will oxidize or dissolve immediately, leaving only aluminum which the solder will not accept. They work great if you just want to use them for what they are. If you plan on opening them up and soldering them, look elsewhere.