UV-500B423FM-OS Offset Duct Board Adaptor Plate for FM Units

Offset Duct Board Adapter Plates for Blue FM Units. Outside Dimensions: ~ 13 7/8" X 8 7/8" X 1 1/2"Recessed Area: ~ 11 3/4" X 6 3/4" X 1 3/8" Notes: This adapter plate is for the Blue FM ballast box and bulbs. If your ballast box is grey, please contact us to order the correct part To mount an FM3 in duct board which contains three bulbs (one UVC / germicidal and one UVV / oxidation on the ballast box and one UVC that is remote) you would need one 500B423FM-OS for the ballast box and one 500423-OS for the remote UVC lamp. This offset plate is not used for installations in metal ductwork.