Vintage item from the 1970's, this is one of the Tricks, Co "Original Magic" series (which also included the Miracle Paddle, available from TMGS).
God Dice involves to small plastic plates (called Flying saucers in the instructions!) which cause a tiny die to repeatedly reappear inside. Die appears, is placed in pocket and reappears. For the finish, the die reappears but it is much larger, filling the inside of the plates.

Good magic, and a very rare Tricks Co item.   This one is in mint condition.   Original instructions included.