Focal Point 21600 5 7/8-Inch Quick Clips System B Inside Corner Block 4-Inch by 4-Inch by 4 1/2-Inch, White Quick and Easy Installation Primed and Ready to Paint or Stain No Need to find Studs and No Nail Holes to Patch Focal Point Corner Blocks eliminate the need to Miter Corners Work with Quick Clip Compatible Moldings and Clips