KOHLER Corbelle 1.28 GPF Single Flush Toilet Tank Only in BlackKOHLER Corbelle 1. 28 GPF Toilet Tank Black The KOHLER Corbelle Toilet Tank is engineered with innovative AquaPiston technology, delivering a fast and effective flush while saving up to 16,500 gallons of water annually. Its sleek black finish adds a touch of modern elegance to any bathroom. Combine it with the K 4144 bowl for a complete and seamless look. Key Features: Efficiency: Uses 1. 28 gallons per flush, offering significant water savings