The battle hood is a reward that can be purchased with tokens from the Fist of Guthixminigame. It degrades with use, similar to the Barrows equipment, and may only be traded when completely degraded. It is currently one of the best magic head pieces available to players. It requires level 50 Defence to wear. It costs 250 Fist of guthix tokens to buy and 25 tokens to charge.
Like all other armours obtained from the Fist of Guthix minigame, it can be degraded for trading purposes by talking to Reggie in the cave and asking him to degrade the item.
When used with a staff of light, and a full set of battle robes, there is 50% chance that you will not use any runes when casting a combat spell.
After a total of 6 hours of combat the robes will be degraded (from 100% to 0%). This won't be affected by how many runes the robes save. This means that using the staff of light will not prolong the lifespan of your robes. This may affect the reason for buying the robes - be it on the Grand Exchange or from Reggie.