Hood pins are security devices that replace the stock latch system on a car hood. They are typically made of steel or aluminum for durability and install on the hood and radiator support panel. Hood pins offer a more secure way to latch the hood compared to the stock latch, especially beneficial for vehicles driven at high speeds or in performance applications where the hood could fly open due to air pressure. When choosing hood pins, consider factors like material, locking mechanisms, and ease of installation.