The Wenger Squire is a retired, keychain-sized 65mm Swiss Army knife with a serrated blade. It is similar to the OptiTool but with a serrated blade. It is actually a bit more common than that model, but both are rather rare.
Size & Weight: The Wenger Squire knife is 65mm (2 1/2") long, 19mm (3/4") wide, and 9mm (3/8") thick. It weighs about 21.0 grams (.7 oz).