Typically this is because it is a good quality but for a great price.
Install vinyl drywall corners.
It is often referred to simply as bead because of the thin straight line that is created with the corner of the material.
Outside drywall corners have traditionally been protected with nail on metal corners but paper faced corner bead is simpler and resists cracks and chips better.
Installing the vinyl corner bead is one of the simplest steps when it comes to the drywall process.
While there are a few different choices when it comes to corner beads vinyl seems to be one of the most popular.
Installed on the outside corners where two pieces of drywall meet corner beads create a smooth even seam and an attractive finish.
Luckily for homeowners installing corner beads and mudding them is one of the easier parts of the drywall process when you install corner beads apply light pressure on the bead itself toward the corner.