Woot offers Amazon Basics Medium Duty Storage Shelving Double Post Press Board Shelf, 36 x 18 x 72 Inch, Aluminum for $49.99 (orig. $125.99). Free shipping for Prime Members. 

Product Description:
From files and supplies to canned goods, tools, and household items, the Amazon Basics shelf is perfect for kitchens, garages, and other areas.
Made of strong, high-grade aluminum with an anodizing finish and press-board shelves, the unit provides simple, dependable storage. A single shelf can support up to 800 pounds, while the complete unit can hold up to 4,000 pounds (when evenly distributed and on a level surface).

• Heavy-duty 5-shelf storage unit (double post); ideal for a kitchen, office, garage, or other space
• One shelf holds up to 800 pounds; whole shelving unit holds up to 4000 pounds (when evenly distributed and on a level surface)
• Durable high-grade aluminum construction with anodizing finish; press-board shelves adjust up or down in 1-1/2-inch increments
• Rivet-lock design for easy bolt-free assembly; instructions and anti-tipping accessories included
• Featuring adjustable height shelves, anti-tip hardware, easy assembly instructions, and a modular design that can be placed side by side or stacked.
• Measures 36 by 18 by 72 inches