Combination seed-and-fertilizer drills are generally classified by their principal function. If seeding is the primary purpose and fertilizer application is ancillary, the machine typically falls under 8432.39. If the fertilizer distribution function is primary, classification under 8432.42 may be more appropriate. When functions are genuinely co-equal, CBP's General Rule of Interpretation 3(c) directs classification under the heading that occurs last in numerical order — which would be 8432.42. A binding ruling is advisable for ambiguous combination implements.

The Netherlands is a global center for greenhouse horticulture and precision vegetable production, and Dutch manufacturers have developed specialized transplanting and plug-seeding equipment for high-value crops. This equipment — designed for lettuce, herbs, flowers, and other transplanted crops — is exported worldwide, including to US greenhouse and nursery operations, explaining the Netherlands' presence among leading suppliers despite its small agricultural land area.