Big Greeting Card Happy Birthday mold.  Has one mold. Reads "Happy Birthday".  Mold measures about 6 1/2 X 4 1/4 inches. 
This would make a nice big bar of chocolate!  Also could be used with plaster to paint and use as gift toppers.  I'm sure you crafty folks out there have even more uses... 
Bottom Marked APOLLO TULSA.
This mold was purchased second hand- so I assume it was used.  Condition is excellent.   Aside from a smattering of surface scratches, no damage found.