Flexmaster Pipe & Tube Joint, 6.00 Inch Pipe, Straight

Four degrees of angular misalignment per end is what this joint is built to handle, so a slight droop or minor offset in a straight run is well within its range. It uses dual compression-style female ends sized for 6-inch pipe with a 6.625-inch OD, so as long as your pipe matches those dimensions, it should fit up without trouble. Just keep in mind the joint itself isn't meant to hold the line in place structurally. You'll still need your hangers, anchors, and guides doing their job to keep the system from moving around.