<table border="1" cellspacing="0" cellpadding="8"><tbody><tr><td>Pipe Class</td><td>Not Rated</td><td>Connectivity</td><td>Welding</td></tr><tr><td>Application</td><td>Heating Systems, hvac & refrigeration systems, plumbing & water supply</td><td>Surface Treatment</td><td>Smooth</td></tr><tr><td>Technic</td><td>Casting</td><td>shape</td><td>Round</td></tr><tr><td>head code</td><td>Square</td><td>Mounting hole diameter</td><td>0.25 in</td></tr><tr><td>customized support</td><td>OEM, ODM</td></tr></tbody></table>