Size: 5/6mm Package Includes:4pcs x Fish Tank Cover Brackets Color: Silver. Quantity: 4pcs/set Material: Stainless steel. designed for use with aquarium glass cover only; do not use these holders for non-intended use. Protect the aquarium cover from damaging while using. Features - Efficaciously prevent the fish from leaping out of the tank or pets to escape. - The premium aquarium clip is made of quality stainless, very durable and convenient. - Install in a second, very easy to use for more convenience if you want to keep fishes. - Help firmly hold the glass cover of the fish tank, assure slipping. - Compact and easy to fasten, providing a safe and protective living environment for your pet.