Product Information Description Measuring Guide Other Details Rosette diameter 1-5/8". Fits all standard 1-5/32" diameter mortise cylinders. Material Color Charts - Click to Enlarge Hewi Door Hardware- Helpful Info Need It Fast? We Can Help! See Our International Shipping Options Request A Quote Today HEWI Cylinder Collar diameter is 1-5/8". Will fit standard 1-5/32" diameter mortise cylinders.