Our 4 Panel SW-38 Solar Water Heating Kit comes with all the parts needed to install your solar water heater system on your house or cabin. As with all our systems they connect directly to your existing water heater and don't interfere with existing source of heat (gas or electric). This way you can enjoy hot water even during long cloudy periods. Using our newly designed SW-38 Solar Water Heater panels you can simply thread the panels together. No more external connection pipes for multi panel installations! Each panel weighs slightly over 14 lbs. and is 24" by 24" but can still provide you with ample hot water. You can begin your system with a few panels and add more if you need more. With this kit you DO NOT have to solder at all!