I have used these for nearly 20 years. Never had a failure, never lost a connection, still have them on my trolling motor, headlights, everything that plugs in. The metal tips are soldered onto the wire you use and then the tip is inserted into the plastic housing and snaps into place. I use the grey ones, SB50's.
http://www.andersonpower.com/products/multipole-sb.html
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