The Dinraal's Scale is an item from The Legend of Zelda: Breath of the Wild. It is used during the "The Spring of Power" shrine quest where Link must obtain it and drop it into the Spring of Power as an offering which causes the Tutsuwa Nima Shrine.
It can be obtained one by shooting Dinraal's body during an airborne encounter or by shooting from certain elevated locations as it passes by. The dragon travels from the Eldin Great Skeleton in the Eldin Mountains through Tanagar Canyon. After being hit, the scale will drop nearby and emits a glow to make finding it easier.
In addition to being used during the Shrine quest, Link obtain more scales or other dragon parts by shooting different parts of Dinraal's body, though he will receive scales only if he hits Dinraal's body and will receive different parts if he shoots Dinraal's claws, horns, or mouth. Link can only obtain a single scale, claw, horn shard, or fang shard from Dinraal per encounter. Dinraal's Scales have a variety of uses such as materials for upgrading certain Armor via Great Fairy. Link can sell them to shops and merchants for 150 Rupees or to Kilton at the Fang and Bone for 60 Mon. It can also be used in Cooking as an additional ingredient to increases the chances of critical success boosting the effects of certain cooked food dishes or Elixirs