Hold On Let Me Overthink This Brain Sticker. Easy to Use: Just peel and stick on a smooth clean surface. Extra durable vinyl, waterproof, sturdy, with strong adhesive. Material: Premium vinyl decal. Durable outdoors for 3 years plus. Lasts indefinitely indoors. Matte finish. *Important Note: Colors vary on different device screens. Therefore, the colors on your sticker may vary somewhat from the colors shown on your screen.