These hexagonal cufflinks are made of carved mother of pearl and have a handsome engraved silver tone edge.  They are marked "Snap Link, B&W Co. Pat'd 1923" and "Kum-A-Part Regst'd Made in USA".  The Baer & Wilde Company produced these snap together cufflinks which were a popular style in the Deco period of the 1920's through the 1930's.   Measures 1/2" across.