Inner Diameter (outside of surround): 7-1/4 inches
Outer Diameter: 8-1/2 Inches
Screw Holes Adjacent Center to Center: 5-5/8 inches
Screw Holes Across Center To Center: 7-7/8 Inches
Depth: 3-7/16 inches
Excellent, previously used condition. Guaranteed to be 100% fully operational.