The Proteus Keychain is a modular holder designed to keep keys together and organized neatly. The system includes a top plate and several bases available in three sizes (regular, large and extra large), with a smooth or knurled finish variant, with a nut hole or with an oversized keyring. Spacers are included to compensate for the thickness of the keys and to adapt the holder even to traditional-style keys. The plate structure allows keys to be added or removed and the bunch to be compacted according to one's needs. The extra large size measures 136.49 mm in length