Convert from arroba [Spain] to quarter (ton) [US]

Unit Definition (arroba [Spain])
The arroba [Spain] is a traditional unit of weight in Spain and Portugal, equal to 1/4 quintal. However, the Spanish and Portuguese quintals are of different sizes. In Spain, the arroba equals 25.36 pounds (11.50 kilograms); arrobas of very similar sizes were established in the Spanish speaking countries of Latin America. The arroba has also been used as a metric unit equal to exactly 15 kilograms. The name of the unit comes from ar rub', Arabic for "the quarter."

Unit Definition (quarter (ton) [US])
The quarter (ton) [US] is a traditional unit of weight equal to 1/4 hundredweight. In the U.S., "quarter" is also used informally to mean 1/4 ton, or 500 pounds (226.80 kilograms).