AR-15 Hand Guards
Free float hand guards are the most popular option. These attach to the barrel nut and do not contact the barrel.
Already have a firearm with an attached hand guard? You will need to disassemble your firearm to install a free float hand guard. If that sounds too daunting, a drop in quad rail or M-LOK polymer hand guard may be what you need.
Hand guards come in different lengths to accommodate different missions. Be sure to order the correct length for your purpose.