All Spike Brewing kettles use NPT (National Pipe Thread) threaded couplers. These threads are tapered and require Teflon tape to make a water tight seal just like the piping in your home. Our Teflon tape is 4mil thick, 1/2" wide and 260" long. Teflon tape is food safe and will stand up to the high heat from a burner. Made in the USA!