Take your markers with you! Store and organize your supplies vertically or horizontally. Interlocking dovetail feature for custom expandable storage that grows as your collection grows! Frame (29003CR) and supplies sold separately. This package contains one 4.25x4x3.625 inch interlocking marker unit with 20 marker slots. Imported. WARNING: This product can expose you to chemicals including 1,3- Butadiene, which is known to the state of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.