Review on Long-Lasting Posi-lock Connectors, 18-24 Gauge, Bulk Pack of 20: High-quality Electrical Wire Connectors for Hassle-free Installations by Kyle Smernes

I like to use these connectors when soldering them isn't practical. I've used them extensively on my bike's wiring and always have extras with me in case I need to fix a wire and don't actually have butt connectors. There are also different types of connectors and I have also used them to connect to other wires. Simply tighten with your finger. I've had some on my bike for 4 and 6 years and haven't had any problems. They are not waterproof, but they can be made waterproof if you use them for a permanent connection. It's very convenient that you need to save me or someone else a wiring glitch.