Smallest is 1.25" while largest is 2". Annie began issuing these in 1935 with Ovaltine's help. This earliest one has nearly complete silver flashing on the outer edge which is quite frequently evaporated. Next from 1936 has secret compartment on the reverse. Brass pin was soldered in position upside down so it makes opening the catch a little difficult but it does function. Next is from 1937. This one has slight luster loss but remains VF. Next is art deco styled 1938 large decoder. Last is the 1940 decoder with date and her initials on the back and the front featuring a beautiful highly embossed graphic of flowing American Flag behind fierce eagle perched on a shield. Four of the five are NM to Mint.