There are some really popular makes, such as Alfa Romeo, Aston Martin, Audi, Volkswagen, and Porsche that aren’t always covered. These vehicles are unique because they feature a top lock wiper arm, (commonly referred to as top-button) which is a slim 16mm wide compared with the standard 19mm top lock arms found on most other vehicles. If you’ve served a customer driving one of these vehicles in the past, you’ve probably had to use a special adapter to install new wipers. Of course, if you didn’t have the adapter, you probably didn’t make the sale.

The following diagram shows the difference in shape and dimensions between a standard top lock wiper arm and the slim top lock (TB16) found on the previously mentioned vehicles.