This is a great BLACK COLORED Transformers Decepticon design dog tag / bottle opener.This can be used as a key chain and includes a 4" Nickel plated 2.4mm silver ball chain.It makes a great fun, and functional gift and is made from aircraft quality anodized aluminum.Measures approximately 2 inches x 1-1/8 inches (about 5cm x 3cm) and have a thickness of 1/16 (.060 thick)