Our technical support team can assist you should you have any questions about your Herrmidifier Dual Pneumatic Atomizing System. Herrmidifier A-17, B-13 and A-33 heads are available in 6, 8, 10, 12 and 15 pounds of water per hour. Water control secions can be AH-1001 or AH-1021 depending upon capacity required. Air control sections can be AH-1000, AH-1020 or AH-1050 depending upon capacity required.