Sized to fit snugly around pipe, these collars have flats so you can turn the collar and your pipe using a standard wrench. This means you don't need to use a pipe wrench, which could scratch the surface of your pipe. These collars are also often used as a stop to support pipe as it passes through floors and walls. They’re also easy to machine, so you can drill and tap a hole through one of the flats to hang a sign. Swing them open to fit over your pipe and tighten them with a single screw—they’re faster to install than two-piece collars. All have captive screws, which won’t fall out of these collars even when fully unthreaded. Made of black-oxide steel, they have some corrosion resistance.

To avoid gouging and marring your pipe while making adjustments, these collars have flats where you can grab and rotate the pipe with a wrench. They're sized precisely for a tight fit around pipe, so they're often used to support pipe passing through floors and walls. They can also easily be machined to hang signs. Since they’re two pieces, you don’t need to have access to the ends of your pipe to install them. Tighten the clamping screws to secure. They’re black-oxide steel, so they have some corrosion resistance.