<ul><li>Made of Aluminum</li><li>Clip on to Key Chains, Handbags, Belts & Back Packs</li><li>1-3/4" Outside Cylinder Length x 3/4" diameter</li><li>1" Diameter Split Key Ring with ~ 3/8" Triangular Link to Screw Cap</li><li>Black non-metalic Washer Seal between Cylinder and Cap</li></ul><br><br>Keychain Pill Holder Comments from Security Engineering not found in labeling: Lightweight Aluminum container with threaded cap and cylinder and compressible washer to keep water and humidity away from contents. Use for Rx pills, Vitamins, OTC pills such as for headaches, Chia seeds for energy, Special Condiments (such as Sugar Substitutes) or For Emergency Cash Storage. If you put a drop of Olive Oil on the threads it will help protect them to avoid oxidation and seizing of the Aluminum threads and waterproof the seal.