8pcs 16 x 50mm Stainless Steel Advertisment Nails Barrel Screws Standoff - Chrome Finish Sign Hardware for Frames #27204 16mm x 50mm Can make the advertisement bolt as your drawings and many size of advertisement bolt. They are easy to install,and secure in use for acrylic sheet, pvc foam board and so on. Widely used in glass, as a Standoff Pin for flush mounted or surface mounted glass attachments. Size:16 x 50mm/0.63"x2"(D*L).