Plumb Pak PP855-69 Air Gap for Standpipes, Grey Fits 1 1/2-inch or 2-inch standpipes, can be mounted at 3 different levels Unit housing length approx. 5 -inch (13.97 cm) Recommended usage 1 to 7 gallons/minute (3.7 to 26.5 liters/minute), tested at 15 gallons/minute (56.8 liters/minute) Allows soft rubber washer hose or washer metal drain hook to share standpipe with other Air Gap units, provides more than twice the code-required minimum air gap opening UPC listed and tested for compliance to IPC and NSF standards