 Once drywall, or any other material, covers the wall it can be difficult to find 2x4 studs for attachment, and the position of nails and screws must be adjusted to stud location.Thus, if blocking is installed at a uniform and predetermined height, attachment sites can be found without using a stud finder, and the blocking can be utilized anywhere along a wall at that height.This is particularly useful for installing upper cabinets in kitchens or bathrooms as they tend to be fairly heavy and finding appropriate studs for installation can be difficult.