Lavinia Stamps - Gel Press - Squarelee. We do not recommend storing the plates with the Mylar sheets that come with them. These are simply part of the post-manufacturing process and can be discarded after first use. Remove the product insert, and store your Gel Press plate in the clamshell packaging. This square Gel Press plate is specially produced for Lavinia Stamps. Size: 4.5 x 4.5 inches.