Upright frames (also known as upright columns but commonly called ‘uprights’) provide a frame for load beams. Simply put, uprights are the bits at the end of the row of racking.
Upright frames are normally made from steel and can vary in size and height. Beams can be attached to uprights by sliding into place, the use of locking pins, bolts and other methods, depending on type of racking.
Holes or slots, sometimes ‘teardrop’ shaped, are inserted along the length of the upright to provide options as to where the beams can be slotted, meaning you can vary the height of shelf layers.