The effect as the instructions state:

The magician displays four white sticks and four blue sticks. Each stick has a number from one to four printed on it. With the numbers hidden the magician sets aside one of the white sticks as his prediction. The spectator selects any blue stick and amazingly the sticks match! This can be repeated over and over. In fact, the spectator can select both sticks and still they match. Includes illustrated instructions. Condition very fine.