Ensure horizontal alignment of pipe flanges with a level rod that runs between two alignment pins. One pin in each pair has a level for vertical alignment. Insert these nut-and-bolt pins into adjacent flange holes and tighten to align flanges before connecting two pipes.

The tapered shaft of these pins eliminates the need for hammering and prying when aligning flange bolt holes. To align bolt holes, fit the tapered end of the pin into the bolt holes and use a wrench on the hex head to rotate and align the holes. If your bolt hole is in between the sizes listed, choose the smaller size pin.

Each step on these aligner pins matches common bolt holes on pipe flanges, so they're more precise than conical aligner pins and don’t require nuts. Press the pair of pins into mated flanges to make sure the flanges are aligned. Once two sets of holes are aligned, you'll know the rest of the holes are as well. Made of durable chrome-plated steel, they'll hold their shape over time and resist rust.