Model: ISO-18-18

Properties:

An item having a major diameter of 3 or more inches (76.2mm) other than items having spoked or sumulated spoked construction, which may be under 3 inches (76.2mm) designed to be gripped by the hand to transmit rotary motion to other devices through a center axis, fabricated in the form of a solid body with simulated spokes or a recessed surface between the rim and the hub, or it may be built up in the form of a frame having a central hub connected to the rim by the spokes. It may have reference markings in the form of dots, arrows, hairline, etc., to indicate the relative position and/or direction of rotation of the item(s) with which it is used. It may also include an integral ratchet device. For similar items having a maximum diameter of less than 3 inches (76.2mm), see knob. For items calibrated in units or series of divisions denoting relative positioning of associated devices, see dial (as modified). Excludes steering wheel.