For safety's sake we added a seat belt with buckles. The plan helps you locate all of the necessary straps and hardware, should you choose to use it. Wood type is recommended to make the highchair just as it is pictured. Truly an heirloom-quality project which will get years of use and become cherished. Super wide base for total stability. Detailed instructions, easy-to-read illustrations, a list of materials used, and a cutting list are all included with this plan. 37" high, x 18" wide, x 18" deep.