Get a Great Start on The Growing Season. These Cold Frames are The Finest in European Design. Weather Resistant with 4mm Polycarbonate Double Skin Panes and a Sturdy Weather-Resistant Aluminum Frame. Easy to Assemble with Easy-Fix-Click-System and Saddle Bag Design. Two Roof Windows, Each Has a Height Adjusters and Has a Child Safe Design with Rounded Edges. Includes 4 Brackets to Hold Windows Open, Adjustable, and Windows Down Against Wind and 6 Ground Stakes. These Cold Frames are UV-Resistant, Has a 10 Year Guarantee Against Yellowing of Panes. Dimensions: 48-inch W by 40-inch D by 16-inch H.