If Weatherpack-style connectors are a little too complicated for you, Painless Performance also offers a high-quality extreme-condition terminal assortment kit. This kit features the finest quality terminals money can buy. High-grade copper, covered in special heat shrink that will not crack under high temperatures. Use a handheld torch to shrink the heat-activated adhesive which in turn creates a waterproof coating around the connection and relieves strain on the wire. We like these because they are impervious to chemicals such as gas, antifreeze, battery acid, diesel fuel, and saltwater.