Item: Vintage Shimano MF-Z012 6-speed freewheel for use on multi-speed road, touring, and mountain bicycles.

Model/Series: Shimano MF-Z012 freewheel produced by Shimano of Japan.

Part type: Thread-on freewheel cluster integrating a ratcheting mechanism and five sprockets for use with compatible rear hubs.

Materials and color: Steel sprockets and body with silver finish on the cogs, darker finish on the central body, and steel internal hardware.

Design details: Six-sprocket stack with progressively larger cogs, perforated largest sprocket with round lightening holes, and splined tool interface at the center for installation and removal.

Features: 6-speed gearing for classic drivetrains, threaded design freewheel hubs, integrated ratcheting mechanism to provide forward engagement and freewheeling coasting, and largest 28T sprocket to provide a low climbing gear option.

Markings and logos: Central dust cover ring is molded with raised 'SHIMANO' logo at the top and 'MF-Z012 JAPAN' text at the bottom, along with additional 'WA' and directional arrow markings; largest sprocket is stamped '28' on the face to denote tooth count.

Actual Measurements: Digital scale display shows an actual weight of 15.2 oz for the freewheel as pictured.

Compatibility: Intended for use on vintage road, touring, and mountain bicycles that accept threaded freewheels and 5-speed derailleur drivetrains; riders and mechanics should confirm hub threading, dropout spacing, chain width, and derailleur and shifter compatibility for their specific setup before installation.

Includes: One Shimano MF-Z012 6-speed threaded freewheel only; no hub, axle, spacers, shifters, chain, or additional drivetrain components are included.