Two cards of vintage "Dainite" rubber buttons, c.1930s

A pair of c.1930s cards of "Dainite Washable and Unbreakable" rubber buttons in "Wavy Bar" pattern, one card each of red and blue buttons respectively, with original cellophane wrappers.  Each button is approximately 2cm in diameter, whilst the cards each measure approximately 10.2 x 16.9cm.  The cellophane wrapper to one packet is split, whilst there is some age discoloration to the cards, and some dust inside the wrappers.  All of the buttons are present and correct, and appear to be in good condition, although, owing to the perishable nature of rubber, we do not guarantee that they are still usable!