Dimensions: overall diameter of this clock insert is 3-1/2 inch/ 90 mm; Fit round hold diameter/ mounting diameter is 3.0 inch/ 78 mm; Mounting depth is 0.6 inch/ 15 mm Clear cover with border: the plastic rim with quartz movement is good for DIY crafts or replacing old clock faces; And the clear cover allows for easily reading the time Rubber band gasket: rubber band gasket of this craft clock insert securely hold the insert in place and allow for slight irregularity in the hole Wide application: plastic rim with quartz movement fits for crafts or replacing old clock faces, round clock insert can be applied to many places Power: this round desk clock insert only requires 1 piece AA battery (not included); Warm note: clock insert is intended for indoor use only, not weather resistant