I like non insulated crimp on connectors, then I cover them with heat shrink. I prefer using the waterproof type so it seals out any moisture. Thomas & Betts or Sta Kon are one of the best crimp on connectors and I’m sure there are others. Stay away from those boxes that contain 200 or more assorted connectors (eBay or Amazon) as they come from China and are thin and much more prone for failure. A good crimping tool is a must. Ratcheting style is great but they can be expensive I have a Kline hand crimper that has served me well for many years. Don’t buy a cheap crimper. It will give you poor crimps and drive you crazy.
Just my cents!
