# Item Modification `item.modification` event is a startup script event that allows you to change properties of existing items ```JavaScript onEvent('item.modification', event => { event.modify('minecraft:ender_pearl', item => { item.maxStackSize = 64 item.fireResistant = true }) }) ``` All available properties: - int maxStackSize - int maxDamage - int burnTime - String craftingReminder - boolean fireResistant - Rarity rarity - tier = tierOptions => { - int uses - float speed - float attackDamageBonus - int level - int enchantmentValue - Ingredient repairIngredient - } - foodProperties = food => { // note: uses functions instead of a = b - hunger(int) - saturation(float) - meat(boolean) - alwaysEdible(boolean) - fastToEat(boolean) - effect(String effectId, int duration, int amplifier, float probability) - removeEffect(String effectId) - }