Floor Corner Base Board Register with Adjustable Air Flow Control Lever Come with Selected Color and Finish (Matte Black - 18inch) actual outsize overall dimensions is

actual outsize overall dimensions is 16“ wide by 8” high

please take off your old floor register and measure the duct hole

buy a 16x25 grille

The Listed size 10"x 3" is for inside duct opening measurement

actual outside dimension is 16" X 16''

Floor Corner Base Board Register with Adjustable Air Flow Control Lever Come with Selected Color and Finish (Matte Black - 18inch) actual outsize overall dimensions is18" long heavy duty steel construction with matte black powder coating finish Simple roundflow design for smooth air flow Easy adjust air flow control with central lever Removable faceplate allows easy cleaning Independent cardboard packing for extra protection