Thank you for your inquiry regarding this item from Prime-Line Products. The flat (seat) surface of this peg only measures 1/2 in. in length. We do manufacture a peg with a 1 in. long seat which is our model number U 9256. You might want to consider a steel shelf support that can be fastened to the underside of the shelf, preventing it from tilting... kindly see model number U 9148. There is another style that may work for you, but the model number would depend on the thickness of your shelves as this style locks onto the shelf's edge. See model numbers U 9391 (1/2 in. shelf), U 9395 (5/8 in. shelf), or U 9398 (3/4 in. shelf).
For additional questions regarding this item, or any other product manufactured by Prime-Line Products, please call their toll free number at (877) 649-9740, or contact them by email at firstname.lastname@example.org