• Standard hex key and tube cutters are all the tools you need • Create tubular frames without welding, threading, bolting or drilling • All you need for a cost-effective, versatile and simple way to design and assemble load-bearing indoor and outdoor structures quickly and easily • Precut pipe is easily fitted and locked in • Galvanized, corrosion-resistant • A cost-effective alternative to welding • Strong and easy to assemble.Mounting Holes are 3/8 and 3/8 in from ends • Mounting holes are 3-1/4 O.C • Pipe hole is 1-3/8 wide / 1-1/2 deep