Sturdy Banana Plugs and the silicone insulation greatly enhance durability and flexibility of the leads that prevents the "memory" characteristic of plastic insulation after it has been rolled/wrapped for a period of time. Plugs fit well into other leads and tests sockets.1M flexible test cable. Voltage: 1000V;Current:15A. Banana Plug: 4 mm. These banana plug leads are stackable. You can plug more than one banana plug into the same banana socket. Kinda like "piggybacking" connections.The banana wires are decent thickness, the ends themselves feel rubberized and not hard slick plastic like some other types of cables you find. They are silicone test lead cables. Wires are very soft , very flexible, very nice to work with. Good test cables for your lab. Every electronic techie out there should have these cables.These are good sturdy leads with thick wires. Good quality leads that work great for moderate to low current testing. These wires are good for up to 15 amps maximum. They are fine for basic elecl testing for things like automotive accessories, vintage cars, trucks and motorcycle, etc, as long as whatever you are testing uses a fuse of 15 amps or smaller.These are useful little leads for all sorts of elecl and electronic work. Add this to your meter bag. when you need a third hand, or have to test many circuits sequentially, this is an absolute necessity. nice silicone insulation and the banana plugs mate easily with a regular bench power supply or a regular meter.