1、These jumpers are made of aluminum and copper materials, which have good conductivity and corrosion resistance. 2、Both ends of the color jumper have been peeled off, and the right‑angle design makes it easier to insert into the circuit board. 3、With a variety of colors, it is easy to distinguish and mark when used, which makes the circuit test more clear. 4、Widely used in the connection of electronic projects, it can be very firmly connected to the pin, no soldering, convenient and fast to use. 5、The kit contains 840 jumpers, with 14 different lengths to choose from, which is highly practical. 840 x Jumper Wires Item Type: Flexible JumperMaterial: Aluminum + CopperJumper Wire Length: 2mm, 5mm, 7mm, 10mm, 12mm, 15mm, 17mm, 20mm, 22mm, 25mm, 50mm, 75mm, 100mm, 125mmApplication: Computers, electronic communications, instruments, meters, industrial program control, digital cameras, MP3, card readers, DVDs, LCM/LCD displays, electronic toys, PCB engineering, PC motherboards, etc.Purpose: Widely used in the connection of electronic projects. It can be used to expand the pins of the experiment board and increase the experiment items. It can be connected to the pins very firmly without soldering, and is used for fast circuit testing.