A berserker helm is members' headgear with decent defence bonuses. To wear it, a player must have 45 Defence and have completed The Fremennik Trials. After the Evolution of Combat, its stats were surpassed by the rune full helm.
With the second Summoning update, a player can have Pikkupstix in Taverley enchant the helm with 35 summoning, at which point it becomes a berserker helm (e) and can hold up to 70 scrolls. When charged it takes on a lighter colour and becomes a berserker helm (charged). Doing this however, removes the strength bonus on the helm.
Many players prefer the helm of neitiznot over the berserker helm, because the helm of neitiznot has better defence with a prayer bonus, as well as costing slightly less than the berserker helm, and also can be obtained free from completing The Fremennik Isles.