Sold as a set. Each set includes: 2 knobs, 2 washers and tube Base plate included with model DG-BT2/23 onlyWARNING: This product can expose you to hexavalent chromium, lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.P65WARNINGs.ca.gov.