A single article is defined as one item of tangible personal property that is considered by common understanding to be a separate unit, exclusive of any accessories or extra parts, and that is capable of being sold as an independent unit or a common unit of measure. The single article laws apply to each commonly understood single item of tangible personal property.
A tractor and related farm implement (e.g., plow, rake, mower, or bucket, etc.) are commonly understood to each be a separate unit that is priced and sold as an independent item. State and local tax would be calculated separately for the tractor and for each implement. The single article local tax limitation and the additional state single article tax are not calculated on a total invoice amount for multiple articles of tangible personal property.
Note that the single article law treats parts and accessories installed on a motor vehicle as part of the motor vehicle. However, this does not apply to tractors.