Ross Gear advertised trucks, not gears, to reach all buyers

National advertising by accessory and parts manufacturers was already common in the auto industry by 1919, and the standard approach was straightforward: advertise the component's own specific virtues to try to win favor with the manufacturers who decided what went into a vehicle. Ross Gear & Tool Company of Lafayette, Indiana made steering gears sold as a component to truck manufacturers, and by early 1919 already supplied 115 of roughly 250 possible truck-manufacturer purchasers, built up through trade-paper advertising and personal selling -- leaving about 135 real prospects remaining.

Ross's problem was structurally three-sided. The truck manufacturer chose which steering gear to install, but a truck dealer had zero interest in steering-gear brand and cared only about selling the finished truck, and the eventual truck buyer was thinking about buying a truck, not a gear. Advertising Ross steering gears directly could win over the manufacturer at best, but had no way to move the dealer or the buyer, the other two audiences whose interest ultimately still determined how many trucks -- and therefore how many Ross gears -- got built and sold.

Advertised the truck industry itself, so one message built demand all three shared, while an X-ray image kept the part present and a booklet captured the interested.

Category ads appeal to all three audiences because each benefits from more trucks sold.

The X-ray illustration kept the gear visible without making it the subject.

The booklet let interested prospects get product details after engaging with the category message.

Ross profited from any truck sale, so category-building was safe even if competitors benefited.

When your sale depends on multiple audiences, advertise the category's value, not your component's features, if you benefit from any sale.

Of the 135 possible truck-manufacturer purchasers remaining on Ross's prospect list before the campaign began, over fifty had adopted Ross equipment within about a year and a few months of national advertising -- and the trade account reporting the results did not overclaim: 'all the credit for this gain cannot be ascribed to the use of Printers' Ink. Aggressive sales efforts played their part.'