Only 8 slats are included, 4 per bed. Additional pack of 18 slats or Bunkie boards or plywood sheets MUST be purchased separately when using regular mattresses. It is safe to use Bunkie mattresses with 8 slats. Need to sleep 2 kids on the floor space of one? This bunk bed is the perfect solution! Made of 100% solid Brazilian pine, its safe, durable and aesthetically pleasing. Have a sleepover guest or need additional storage or protection for a little baby? Optional compatible trundle, drawers and safety rail guard will accomplish just that!Overall Size: 80.25 inchl x 48.25 inchw x 61.75 inchh Bed Size: Twin over Twin Paint Finishes:Mahogany, Gray, Java 40% gloss Color/Wood Samples: Actual color may vary. Wood samples mailed out for color matching upon request Construction & Features: 8 twin size slats included 1 inch thick rails Metal-to-metal rail to post secure connections 2.5 inch by 2.5 inch posts 31 space between top and bottom beds Can be separated into two twin beds Fits standard twin mattresses 39w x 75l up to 8.5 high.