Even though your uniform items at boot camp are issued (free), many items are not. Your first night at boot camp you are given a number of hygiene items, shoe polish, sewing kit, t-shirts, PT-Shorts, sun tan lotion, some other miscellaneous items plus $150 Chit book for the Navy Exchange. This will cost you about $450 from your first pay check. A good $60-$80 of that chit book will be spent within the first week buying extra items from the exchange that you'll need for the rest of boot camp (most of it being more shirts, underwear, etc.)