The Proteus Keychain is an interlocking key holder, made up of upper and lower plates and spacers of various sizes. The closing screws hold the two shells together, while the 1, 1.5 and 2 mm spacers allow the thickness to be adapted to the keys inserted. The system is available in three sizes (regular, large and extra large) and in variants with a knurled base or with a nut, including for thick keyrings. The extra large model measures 136.5 mm in length. Once assembled, the keychain gathers the keys into a single compact and tidy block, preventing them from jingling or getting tangled in a pocket or bag