This is a set of 8 dice, six are weighted, covering a dice for each of the six sides of the dice - two are regular matching dice. 

Used correctly, these are a great accessory for the magician.  A typical routine...have a dice examined, place the dice into a cup and hand to a spectator, now reach into your pocket and remove a pen and paper to write a prediction.  The spectator rolls the dice, the prediction matches.  This can be repeated with a different number.  Note: Loaded dice are not 100% falling on the forced side, so you should be prepared with an out for when this happens