G.T. Water Products, Inc. LTP34SB Safe-T-Seal Long Test Plug, Smooth Body, Fits 3-Inch to 4-Inch Pipes Fits 3-Inch to 4-Inch pipes and has a smooth body Long test plug with 2 stage deflation prevents backsplash and includes 4-Foot extension hose Used to test water lines in new construction and renovation projects A patented pressure release safety valve to help prevent over inflation or blow-out Made in the U.S.A.