A security seal is a device that is used to secure and tamper-evident closure on a package. It is designed to provide evidence of unauthorized entry or tampering, and it is often used to protect against theft, damage, or tampering during transportation or storage. There are many different types of security seals, including cable seals, bolt seals, plastic seals, and metal seals. Some security seals have unique serial numbers or other identification marks, which can be used to track the seal and provide additional security.