A Pokemon GO Evolution Item is required to make certain Pokémon evolve. Trainers can collect Evolution items by spinning PokéStops. Drop rates for evolve items are fairly low (0.76% – 1%). However, trainers can get 1 guaranteed, albeit random, Evolution Item by completing their “First PokéStop of the Day” 7-day streak.

There are currently 5 Evolution Items available in Pokémon Go:

Sun Stone King’s Rock Metal Coat Dragon Scale Up-Grade
 Bag_Sun_Stone_Sprite.png  Bag_King's_Rock_Sprite.png  Bag_Metal_Coat_Sprite.png  Bag_Dragon_Scale_Sprite.png  Bag_Up-Grade_Sprite.png
In-game text: A peculiar stone that can make certain species of Pokémon evolve. It burns as red as the evening sun. In-game text: A rock that can make certain species of Pokémon evolve. It looks like a crown. In-game text: A coating that can make certain species of Pokémon evolve. It is a special metallic film. In-game text: A scale that can make certain species of Pokémon evolve. It is very tough and inflexible. In-game text: A transparent device that can make certain species of Pokémon evolve. It was produced by Silph Co.

The table below shows Evolution Items and the related Pokémon to evolve:

Evolution Item Pokémon to Evolve Candy Cost Evolved Form
Sun Stone Gloom 100 Oddish Candies Bellossom
Sun Stone Sunkern 50 Sunkern Candies Sunflora
King’s Rock Slowpoke 50 Slowpoke Candies Slowking
King’s Rock Poliwhirl 100 Poliwag Candies Politoed
Metal Coat Scyther 50 Scyther Candies Scizor
Metal Coat Onix 50 Onix Candies Steelix
Dragon Scale Seadra 100 Horsea Candies Kingdra
Up-Grade Porygon 50 Porygon Candies Porygon2

Note: Pokémon requiring Evolution Items are not typically found in the wild.

Evolution Items are used for both normal and split evolutions:

 Normal Split
 

Check out these guides to find out more about Evolution Items: